Develop Bugs

[Q] Dual sim adapter

Hi all,
As anyone ever tried dual sim adapter on our phone?
Regards
Gaarapt

Which phone model?

from i5800 and i5801 probably he means as model .

hmm, interesting...is it possible to do it? would be a great help, if someone please post some info about it.

Yea i work at my brothers local phone shop and we use these all the time. I've used it on those phones without any issues. If you want to PM me i can point you to where i get them from?

dual sim ?
RHOUSMAN said:
Yea i work at my brothers local phone shop and we use these all the time. I've used it on those phones without any issues. If you want to PM me i can point you to where i get them from?
Click to expand...
Click to collapse
hey there...Can u give me info about dual sim adapter for our g3
like how it works and where to get ?

dual sim ?
RHOUSMAN said:
Yea i work at my brothers local phone shop and we use these all the time. I've used it on those phones without any issues. If you want to PM me i can point you to where i get them from?
Click to expand...
Click to collapse
hey there...Can u give me info about dual sim adapter for our g3
like how it works and where to get ?
i cant believe it is possible..

here is the video about duel sim adaptor...YouTube

I have never ever seen an Android phone with a dual sim... But I want to

this could be very functional. and could save a lot of time switching cards.

there are a few dual sim android phones like http://www.fonearena.com/blog/33946/motorola-xt800-dual-sim-android-phone-review.html
but only 550mhz cpu...
all the dual sim androids are gsm+cdma
sadly these dual sim adapters cant do dual sim standby....
meaning u cant call or recieve calls and sms when u select the first sim on the second sim

ak700 said:
I have never ever seen an Android phone with a dual sim... But I want to
Click to expand...
Click to collapse
Check out Motorola XT800. Its dual SIM (GSM+CDMA) phone, but too expensive for its specifications.
http://www.gsmarena.com/motorola_xt800_zhishang-3073.php
EDIT: unreal3000, didn't notice that you too provided a link of the same model.

would this be a form of plug and play or would you need to solder it on mobo of the phone?

nsm1234 said:
Check out Motorola XT800. Its dual SIM (GSM+CDMA) phone, but too expensive for its specifications.
http://www.gsmarena.com/motorola_xt800_zhishang-3073.php
EDIT: unreal3000, didn't notice that you too provided a link of the same model.
Click to expand...
Click to collapse
xD no prob! i first found it strange reading ur post! then realized i ddnt mention
which phone the link was!

!
hasjee said:
would this be a form of plug and play or would you need to solder it on mobo of the phone?
Click to expand...
Click to collapse
none of them need soldering...but most of them require you to cut both the sims
to make them smaller...dont worry it wont damage the sim and they give u an adapter incase you want to use the sims again....but the ones which can use 3g are much more expensive!

cutting them in pieces to make em fit wont be a prob, you could always get a new sim with your old phone number. and that it doesnt require soldering is a BIG +++ to this. im getting more and more interrested.

From my experience (and i have a fair bit) its a piece of cake. Never had any issues what-so-ever

With such a dualsimadaptor do you have to reboot to use the other sim or can you switch between the two simcards when your phone is on?
sorry for my noob question

Blackyx007 said:
With such a dualsimadaptor do you have to reboot to use the other sim or can you switch between the two simcards when your phone is on?
sorry for my noob question
Click to expand...
Click to collapse
no reboot!

Intresting....

Dual sim for galaxy s2

I surfed over internet and accidentally see this :
http://www.youtube.com/watch?v=McpwWmEtT8w
Sorry if this thread is posted allready...

promising but confused to how an O2 sim card shows as Swisscom and not O2 *country*?

Avoid simore like the plague.
There's much more reliable options out there for this. I've wasted a lot of money with Simore in the past. My advice is Magicsim 28th PLUS off ebay
Hope this helps!

Does anyone have any advice on a good place to get a dual sim adapter from for the galaxy S2?

I'd be interested in this too....anyone?

Looks really good. Sadly no videos nor pictures yet but I'll keep this in mind. How do you switch between sims?

Well I switch sims on the stk menu by just selecting which sim I want active but you can also set it to switch sims at a set timed interval. E.g. 60mins on sim 1, 10 mins on sim 2

sophiewyles said:
Ok so i ordered the 28th no-cut one from magic-sim.com in the end as it required no sim modification and just sits in the phone under the battery.
It's working well
Click to expand...
Click to collapse
How the 'connections' r like with the adapter? do u lose signal or anything?

sophiewyles said:
Ok so i ordered the 28th no-cut one from magic-sim.com in the end as it required no sim modification and just sits in the phone under the battery.
It's working well
Click to expand...
Click to collapse
Under the battery? And the back cover close well?
Can you post a photo? Thanx!

Connections been absolutely fine. Not noticed any issues with that at all.
It fits fine under the case....easy enough to close and didn't require any excess force or anything like that.

can someone post a picture?

Some photos please!
Thanx!

woops for some reason the pics didnt attach... I'll try again...

Thanks for the pic. Looks really good.
Are there a lot of options in the app?

Well following sophiewyles advice I got a dual sim adapter for my galaxy s2 from www.magic-sim.com
It's been working really well sim switching is easy and very quick. No complaints here!
Dave

Quick question do any of you have the official samsung extended battery? If yes does it fit with the dual sim adapter?

Carnelain said:
Quick question do any of you have the official samsung extended battery? If yes does it fit with the dual sim adapter?
Click to expand...
Click to collapse
Yes, it fits with the 2000 mAh battery too.
But I have a small problem with it:
- after switching between the cards the APN settings are not changed automatically, so internet connection is gone. I have to reboot each time
I use T-mobile (private) and Telenor (office). If on T-mobile, the T-mobile APN-s are active, but when I switch to Telenor, the T-Mobile APN settings stay there and can even not change manually. After reboot it is OK with Telenor. Phone calls are not affected from APN-s, so they are working without problems.
Any idea?

I just do a reboot every time, no big problem since reboots are so quick. Unless the Blackberries which literally takes 5 minutes..

chiefroastbeef said:
I just do a reboot every time, no big problem since reboots are so quick. Unless the Blackberries which literally takes 5 minutes..
Click to expand...
Click to collapse
any shortcut (widget) for reboot i know i off limit on this discussion

Thanks doongoo.

Sim Card Removed - Restart/Reboot Phone

Hi there
i own a galaxy S3 TMobile version for 2 months now.
I recently update on last rom and since then i am getting the following error.
Sim card removed. Replace the sim with a valid sim and restart/reboot the phone.
I am not really sure if i wrote the message exactly as it appears but thats the meaning of it.
I have unlocked the phone to use it on Greece.
I have the same sim on it, since the beggining.
I didnt had the problem before the update. And for sure the problem poped up some days after the update.
When i see that msg the most of the times (if not always) data is enabled.
I should also say that when i see that msg the phone is just sitting untouched. Phone has never dropped or anything like that.
For sure its annoying.
When i restart phone sim is working perfectly...... ..
Has anyone heared about it? Anyone who faces the same prolem and found a solution?
I tried to google it ut i came up with no answers...
Any help is welcome.
Thank you in advance

have u tried a different SIM yet?
Sent from my SGH-T999 using xda premium

I had the same kind of issue on my previous phone. However, there is no data on my phone that I had to reboot my phone a few times to establish data connection. Secondly, sometime I missed called. Replacing SIM card may not help either. A few people had reported the same kind of issue on T-Mobile Support site.
Leoniums said:
Hi there
i own a galaxy S3 TMobile version for 2 months now.
I recently update on last rom and since then i am getting the following error.
Sim card removed. Replace the sim with a valid sim and restart/reboot the phone.
I am not really sure if i wrote the message exactly as it appears but thats the meaning of it.
I have unlocked the phone to use it on Greece.
I have the same sim on it, since the beggining.
I didnt had the problem before the update. And for sure the problem poped up some days after the update.
When i see that msg the most of the times (if not always) data is enabled.
I should also say that when i see that msg the phone is just sitting untouched. Phone has never dropped or anything like that.
For sure its annoying.
When i restart phone sim is working perfectly...... ..
Has anyone heared about it? Anyone who faces the same prolem and found a solution?
I tried to google it ut i came up with no answers...
Any help is welcome.
Thank you in advance
Click to expand...
Click to collapse

I tthought I was the only one plagued by this issue..
I have this same issue. It usually happens whenever I lose network coverage......it happens repeatedly.. This issue started happening after I updated to jelly bean...ICS had no problems..
I have changed my sim 3 times, installed several touch wiz custom ROMs, changed my base bands and kernel...The issue remains prevalent after all these..
The only way I have been able to resolve this issue is by switching to an AOSP ROM like cm10 or paranoid android rom
I hope a fix for this issue is found soon cos i am tired of restarting my phone everytime i lose network coverage
I have attached a screenshot showing this

replacement sim ractified the problem
Leoniums said:
Hi there
i own a galaxy S3 TMobile version for 2 months now.
I recently update on last rom and since then i am getting the following error.
Sim card removed. Replace the sim with a valid sim and restart/reboot the phone.
I am not really sure if i wrote the message exactly as it appears but thats the meaning of it.
I have unlocked the phone to use it on Greece.
I have the same sim on it, since the beggining.
I didnt had the problem before the update. And for sure the problem poped up some days after the update.
When i see that msg the most of the times (if not always) data is enabled.
I should also say that when i see that msg the phone is just sitting untouched. Phone has never dropped or anything like that.
For sure its annoying.
When i restart phone sim is working perfectly...... ..
Has anyone heared about it? Anyone who faces the same prolem and found a solution?
I tried to google it ut i came up with no answers...
Any help is welcome.
Thank you in advance
Click to expand...
Click to collapse
I had the same problem the other day when I was driving home from work. I think it happened when I went from 4G to 2G coverage. And also, when I'm in 2G coverage, signal fades out completely and comes back on 10 secs or so later. I went to Tmobile and replaced my sim with a new one and I had no problem of such ever since. .. at least so far so good.

droidNoob74 said:
I had the same problem the other day when I was driving home from work. I think it happened when I went from 4G to 2G coverage. And also, when I'm in 2G coverage, signal fades out completely and comes back on 10 secs or so later. I went to Tmobile and replaced my sim with a new one and I had no problem of such ever since. .. at least so far so good.
Click to expand...
Click to collapse
just restore to stock , and you can use it

thecat1102 said:
just restore to stock , and you can use it
Click to expand...
Click to collapse
Believe me I have Odin end back to stock n the issue still persists.....changing sim cards is only a temporary solution....
The problem always comes back especially if you always in an area with no network signal

Warranty exchange! Samsung should replace it. Say won't read sim card. Or tmobile
Sent from my SGH-T999

It seems that it happens when the data signal is bad.
Yesterday i had to reboot more than 3 times inside in a 4h period.
Wth........

First & foremost,
How did you "unlock" your phone? Did you mess with the NV data??
Or were you a good boy & had T-Mobile do it for you?
It sort of sounds like T-Mobile may have disabled your SIM card altogether....which may happen if you screwed around with the NV data.
If it was properly unlocked by T-Mobile you should be able to stick whatever SIM card in there now. Easy to test, go down the street to your nearest Greek mobile telecom store & ask if you can test a prepaid SIM card in your phone. Assuming the GSM networks are to some degree similar to the US T-Mobile networks, you should even be completely in good shape using local GSM service.
*IF* you get the same issues with the local SIM card....well screw it then. Go protest in the streets about the austerity measures in effect at the moment. Or just be a lazy Greek bastard & demand 14 months salary paid, require retirement at age 50 and lastly *NEVER* pay property tax on anything.
/rant
Besides, you're in a marvelous country full of great food, drinks, parties and oh yeah nice women too. No Yiayia's tho.
Wtf you wasting time on stupid phones for hehe

puretone said:
How did you "unlock" your phone? Did you mess with the NV data??
Or were you a good boy & had T-Mobile do it for you?
It sort of sounds like T-Mobile may have disabled your SIM card altogether....which may happen if you screwed around with the NV data.
Click to expand...
Click to collapse
Well i have unlock the phone through internet. I had no issues for the past 2 months at all and yes i am using a local sim card from the beginning. The problem came up with the last upgrade!
Besides that i have a backup of the nv data but i am pretty sure that isnt the problem.
puretone said:
*IF* you get the same issues with the local SIM card....well screw it then. Go protest in the streets about the austerity measures in effect at the moment. Or just be a lazy Greek bastard & demand 14 months salary paid, require retirement at age 50 and lastly *NEVER* pay property tax on anything.
Click to expand...
Click to collapse
LOL? What is that? Everyone around the world is talking about the Greek people and have no clue of what it really happens. I work 12-14 hours per day including weekends.... i pay more than 600 Euros on taxes per month and i ll never get those money back since retirement is at 70 yo!!! Most of the people are like this. Foking politicians and goverments who have been stealing money for so many years. That was the problem and not the people!
I wish i knew why you mention all these!

sim card removed
I'm having the same issue with my s3
I tried to unlock it using this method
http://forum.xda-developers.com/showthread.php?t=2014982
I'm not sure if it worked, but perhaps messing with NV data screwed something up??
I upgraded to jelly bean 4.1.1
I tried cleaning the contacts on the sim
I replaced the sim at WIND
I even tried a factory reset
Nothing worked so far.
Has anyone figured out why it's doing this? Is it hardware related? software related?

vivamente said:
I'm having the same issue with my s3
I tried to unlock it using this method
http://forum.xda-developers.com/showthread.php?t=2014982
I'm not sure if it worked, but perhaps messing with NV data screwed something up??
I upgraded to jelly bean 4.1.1
I tried cleaning the contacts on the sim
I replaced the sim at WIND
I even tried a factory reset
Nothing worked so far.
Has anyone figured out why it's doing this? Is it hardware related? software related?
Click to expand...
Click to collapse
In the same boat as you...I thought i was the only one..
on wind's sgh-t999v Galaxy SIII ... unlocked it like you did, and I'm getting a no sim card, restart required error, get it about every 8 hours or so..
i ported my number over too, but it says under "my phone number" in settings.. has a completely different number than what I'm currently using.. not sure if that has any effect..
tried restoring to factory settings too.. nothing seems to work...
if anyone has any info that would be much appreciated...

From the cold boot and after the error message goes away, does your phone has data connection?
I got the same error message on my previous phone. However, it would not establish the data connection.
Watch this video to see if your phone behaves the same way --> http://www.youtube.com/watch?v=GRB-cPD-JlE
yee_fun said:
In the same boat as you...I thought i was the only one..
on wind's sgh-t999v Galaxy SIII ... unlocked it like you did, and I'm getting a no sim card, restart required error, get it about every 8 hours or so..
i ported my number over too, but it says under "my phone number" in settings.. has a completely different number than what I'm currently using.. not sure if that has any effect..
tried restoring to factory settings too.. nothing seems to work...
if anyone has any info that would be much appreciated...
Click to expand...
Click to collapse

VibrantThemer said:
From the cold boot and after the error message goes away, does your phone has data connection?
I got the same error message on my previous phone. However, it would not establish the data connection.
Watch this video to see if your phone behaves the same way -->
Click to expand...
Click to collapse
mine doesn't do that, I have a data connection almost instantly where I have a signal
the error goes away after a reboot, but the error stalks you, and you never know when it's going to strike..
sometimes when it's in my pocket waiting for a call, while i'm driving with a headset on, at night while i'm asleep
for me, it isn't consistent, but it eventually happens..
I intend on taking it to the repair center for wind next week once I get back home (with the family for the holidays)

I don't think this issue has anything to do with if the NV data was messed with because my husband and I have the same phone purchased the same day 6 months ago. We both get the same error message and it's does not always happen at the same time so I am not sure it has anything to do with the network either. When it happens to him, he tells me it's happening but it does not happen to me. I googled the error because it is annoying. I will guess now that this issue has to do with the Gallaxy s3 and the update to the firmware. I can't wait for a better update.
puretone said:
First & foremost,
How did you "unlock" your phone? Did you mess with the NV data??
Or were you a good boy & had T-Mobile do it for you?
It sort of sounds like T-Mobile may have disabled your SIM card altogether....which may happen if you screwed around with the NV data.
If it was properly unlocked by T-Mobile you should be able to stick whatever SIM card in there now. Easy to test, go down the street to your nearest Greek mobile telecom store & ask if you can test a prepaid SIM card in your phone. Assuming the GSM networks are to some degree similar to the US T-Mobile networks, you should even be completely in good shape using local GSM service.
*IF* you get the same issues with the local SIM card....well screw it then. Go protest in the streets about the austerity measures in effect at the moment. Or just be a lazy Greek bastard & demand 14 months salary paid, require retirement at age 50 and lastly *NEVER* pay property tax on anything.
/rant
Besides, you're in a marvelous country full of great food, drinks, parties and oh yeah nice women too. No Yiayia's tho.
Wtf you wasting time on stupid phones for hehe
Click to expand...
Click to collapse

Hi again
Since I know that there are a lot of people facing the same problem I thought it would be nice to give the solution on this kind of problem.
It seems that when you update via kies (of course on stock roms) something goes wrong. Recently I install the latest rom using odin and except that I found so many new things that I couldn't see before I also had no sim problem again.
So I am pretty sure that this kind of problem appears due to the kies updates. And from what I saw there where more.
If anyone else try the same please let me us know if it worked.
Good luck to u 2.
Btw yes I had that problem when the data signal was almost 0... Maybe 0.... Only then!
Sent from me

puretone said:
Besides, you're in a marvelous country full of great food, drinks, parties and oh yeah nice women too. No Yiayia's tho.
Wtf you wasting time on stupid phones for hehe
Click to expand...
Click to collapse
First of all I want to ensure you that has nothing to do with the way I unlocked the phone.
Second nv data is untouched.
3rd the problem came on after an update.
As I said after a clear fresh install without ba kups etc, starting from 0 the phone works great again and also there are options settings etc that I couldn't see before. Crazy but real. If anyone else do the same thing and make a fresh install with the latest rom he will agree with that.
So... As you said we make good parties and have nice womens... But how you will caption those moments those special (girls) moments without a nice camera (phone) ?
Have a good day hehe.
Sent from my SGH-T999 using Tapatalk 2

For those on the SGH-t999v version of the phone... the reason you are getting this "no sim error" is because of the firmware update to 4.1.1. I've sent my phone in for repairs and the best answer they could give to me was that there's an issue with the current jellybean.. not sure about the SGH-t999 standard versions though...
Unfortunately, I've had to revert back to ice cream ....and guess I have to wait till Lime Pie (OS 5) comes out...
The issue is not the NV data as I have used that method to unlock my phone as well.

Thank you for your replies. I'm relieved to know that it is not the nvdata menu that caused this problem.
I sent my phone in twice now and I've recieved it back for the second time today.
The first time resulted in further Sim card error messages. I'm keeping my fingers crossed in hopes that it does not appear again.
If op would be so kind to lead me to the right direction as to how to use Odin, I'd greatly appreciate it.

Data blocked on phone sim when used on Tablet

Hi I wanted to know is there a bypass or trick or app to make the Internet work via a mobile sim.i wanted to use the t705 as a phone.the text works but data doesn't.
I get a message saying I can't use sim in a tablet.

What network you using chief?
if its Three, then its a bit awkward. you can either use a tablet sim which works but with no voice or texting, or you use a phone sim which uses voice and text but data dosent work.
i believe as the phone sim picks up the tablet as a "tethered device" (i think because the Tab-s identifies it to the sim somehow obviously as a tablet which three dosent seem to allow.)
frustrating as hell really.
i have used an EE sim in my tab -s and seems to work with voice, date and text. but cant speak for any other sims (ill have to try my VM staff sim and will report back)

aikon359 said:
What network you using chief?
if its Three, then its a bit awkward. you can either use a tablet sim which works but with no voice or texting, or you use a phone sim which uses voice and text but data dosent work.
i believe as the phone sim picks up the tablet as a "tethered device" (i think because the Tab-s identifies it to the sim somehow obviously as a tablet which three dosent seem to allow.)
frustrating as hell really.
i have used an EE sim in my tab -s and seems to work with voice, date and text. but cant speak for any other sims (ill have to try my VM staff sim and will report back)
Click to expand...
Click to collapse
I'm using three.so with ee it works fine . because with certain networks it works for a while then stops, I'm thinking shall I switch to ee.also is there some file that can be edited so the network recognise the device as a phone not tablet?

adamo86 said:
I'm using three.so with ee it works fine . because with certain networks it works for a while then stops, I'm thinking shall I switch to ee.also is there some file that can be edited so the network recognise the device as a phone not tablet?
Click to expand...
Click to collapse
I've just discovered this very same problem, and had a very long conversation with three, who sadly aren't able to offer me anything!
I doubt that there will be anything that can spoof three in to thinking that their sim is being used in a phone, as it will likely mean providing a fake ime number etc, however, if there is a way, I'm all ears... If not, I guess I'm changing to EE

I roughly use 25gb of data so ee is to expensive for me.

Damn, thats a lot of data a month! Yeah, EE will definitely be no good for that. I ended up speaking to EE about the situation, they were of the same opinion as me, in that it seems crazy why you cant put your sim into what ever device you like and use it how you like. Consequently, they specifically told me that should I choose to put my EE phone sim into my tablet, they will be absolutely fine with it.
EE have themselves a new customer, three are a man down. Shame, as I actually really rated three. Hopefully they will see some sense in the near future

dannstarr said:
Damn, thats a lot of data a month! Yeah, EE will definitely be no good for that. I ended up speaking to EE about the situation, they were of the same opinion as me, in that it seems crazy why you cant put your sim into what ever device you like and use it how you like. Consequently, they specifically told me that should I choose to put my EE phone sim into my tablet, they will be absolutely fine with it.
EE have themselves a new customer, three are a man down. Shame, as I actually really rated three. Hopefully they will see some sense in the near future
Click to expand...
Click to collapse
Giffgaff also allows using phone sim in tablets which can be used as phones only like tab s

adamo86 said:
Giffgaff also allows using phone sim in tablets which can be used as phones only like tab s
Click to expand...
Click to collapse
I had to leave O2 prior to joining three.... although most of the time it would show a full 3g signal, I'd get absolutely no data through most of the time... gift gaff just piggyback off their massively overcrowded network

I'm going to get it for a test drive.i left o2 ages ago because when I had a HTC hd 2 it didn't have a toggle to turn off data and my data would get used up eventually bard I explained to them how the phone was they didn't care later some developer made an app to toggle data off.

Note 10+ 5G Unlocked N976U stopped macking/receiving calls ATT

Hi guys,
My Samsung Note 10+ stopped making receiving calls about two weeks ago.
I have no option for VoLTE if that was the case; I updated my firmware to the last available (Android 12). I called customer service, and they did their "magic" with my IMEI and ID e t. c. I also went to their office, and they said they couldn't help me, but they have customers with the same issues with non-att phones.
Any solutions?
Thank you!

It's whitelisted.
*#*#4636#*#*, device info, enable VoLTE provisioned.

blackhawk said:
It's whitelisted.
*#*#4636#*#*, device info, enable VoLTE provisioned.
Click to expand...
Click to collapse
Thank you for your reply.
VoLTE provisioned is inactive.
Please, see the screenshot attached.
How can I activate it?

Not sure, but that's the problem.
Did you get a new sim card for it?

I got it a year and half ago. I will replace it today just in case.

Konfl1kt said:
I got it a year and half ago. I will replace it today just in case.
Click to expand...
Click to collapse
The sim card needs to be configured for 4 VoLTE.
My N10+ was already running it, nothing happened after the switch.

Just got a new Sim. Nothing changed.
Still can't make and revcieve calls.

Konfl1kt said:
Just got a new Sim. Nothing changed.
Still can't make and revcieve calls.
Click to expand...
Click to collapse
Was this originally an ATT phone?

No, originally Samsung US version, unlocked.

I have a N975U1 and a new N975U. These are both 4G only variants, no 5G*.
The N976U however is whitelisted by AT&T and should work.
I haven't fully configured the unlocked variant so after reading this thread I was wondering what it do. It hasn't been booted since the switch.
Slammed it the sim card and booted; it's working the same as it's sister.
Try clearing the system cache.
Network reset.
Reset on AT&T's side.
*5G Versions: SM-N976F (Global); SM-N976U (USA); SM-N976N (South Korea)

Thank you. My version is the US version. All those things are done. I think I will change the carrier. ATT is just doing nothing.

Konfl1kt said:
Thank you. My version is the US version. All those things are done. I think I will change the carrier. ATT is just doing nothing.
Click to expand...
Click to collapse
Something is misconfigured.
It may be the new sim card or ithe sim card may be damaged; install a new one yourself and handle it like a stick of ram, it's ESD sensitive.
Talk to Advance tech support at AT&T, get someone that knows what they're doing... may take a few tries.
Also clear the data in the sim toolkit app in addition to what I already suggested.
Try a hard reboot as well.
Access point names settings should be this:

blackhawk said:
Something is misconfigured.
Click to expand...
Click to collapse
I can't add NXTGENPHONE or ENHANCEDPHONE. It disappears right after saving.
There are many people with the same issue on the ATT forum. Many of them spent days talking to the support team; I tried it four times already and went to their office twice. Nothing helps, unfortunately.

Konfl1kt said:
I can't add NXTGENPHONE or ENHANCEDPHONE. It disappears right after saving.
There are many people with the same issue on the ATT forum. Many of them spent days talking to the support team; I tried it four times already and went to their office twice. Nothing helps, unfortunately.
Click to expand...
Click to collapse
I think the problem is the sim card.
On my unlocked new N10+ variant all I did to set it up was slam in the sim card from my other AT&T N10+. I didn't touch any settings on it.
How to set up Access Point Name (APN) on Samsung Mobile? | Samsung SG
FAQ for Samsung Mobile. Find more about 'How to set up Access Point Name (APN) on Samsung Mobile Device?' with Samsung Support
www.samsung.com

blackhawk said:
I think the problem is the sim card.
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Yesterday, I got a new one—the same story with two sim cards.

Konfl1kt said:
Yesterday, I got a new one—the same story with two sim cards.
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Check the card and make sure it's seated properly...

blackhawk said:
Check the card and make sure it's seated properly...
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I did. The first card I tried to clean with alcohol as well. It stopped working overnight. The new one I tried to reinstall twice.

Konfl1kt said:
I did. The first card I tried to clean with alcohol as well. It stopped working overnight. The new one I tried to reinstall twice.
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Maybe the phone side contacts.
I will remind you again the these circuits are suspectable to ESD damage. May fail instantly or days, weeks, even years latter.

Konfl1kt said:
I did. The first card I tried to clean with alcohol as well. It stopped working overnight. The new one I tried to reinstall twice.
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After reading all of this, the only thing I have seen in regards to ATT not making calls is with WIFI calling if it does not have the carrier bloat.
You may have fun trying to find the user data file for ATT to flash for N976U.
If you could, load the carrier bloat U package and see if it resolves the issue.
The only other thing I have seen is when ATT deems a phone incompatible, they just suspend the SIM card and make it inactive. If the phone is whitelisted it shouldn't do this.
The best thing would be to go with someone like T-Mobile who won't mess with your SIM etc.

yygemmi770 said:
You may have fun trying to find the user data file for ATT to flash for N976U.
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I did. I found it here. I tried different firmware. Nothing helps. I already ordered 22 Ultra. I didn't want to upgrade now, but I can trade in my old galaxy. In this case, it's acceptable for me.