Develop Bugs

Help unlocking GALAXY S II Mexcian Carrier to UK. UNUSUAL PROBLEMS

Hi, first post here. I need help unlocking my Samsung Galaxy S2.
Details of the phone:
Android Version 2.3.7
Baseband version: I9100UMKG2
Kernel version
2.6.35.7-g1e46077
[email protected]#1
Mod Version
CyanogenMod-7.1.0-GalaxyS2
Build Number
GWK74
IMEI:
***
So, I went to an unlocking place in London, were they used all kinds of software that would supposedly unlock it, but it didnt work on any different carrier other that the one I have it on. I have a plan on TELCEL from Mexico for 18 months. I tried a second place and they still couldnt do it, even with the Samsung Software. So I rooted it, flashed it, and put CyanogenMod in it, and downloaded two apps that supposedly unlock it, one was the app done by ChainFire, and the other one by helroz. The chainfire app couldnt find the code! Helroz did nothing after it restarted. Also, I tried putting a code but only twice, so the phone still works fine and has chances for the unlock left, I believe.
One important thing to note is that with the old software that came with the code it wouldnt even as for an unlock code, but after rooting and putting cyanogen mod in it, it asks for an unlock code. Thats basically all ive done to it.
So, is there any way I can unlock this phone? And has there been cases were a phone is just impossible to unlock no matter what you do? I am desperate here!

Please remove your IMEI
Sent from my R800i using xda premium

AwaisKhan said:
Please remove your IMEI
Click to expand...
Click to collapse
Good call. IMEI's should never be shared publicly on the internet.

TeeJay3800 said:
Good call. IMEI's should never be shared publicly on the internet.
Click to expand...
Click to collapse
You dont know what people could use them for, lol
Sent from my R800i using xda premium

ok sorry about the IMEI ,and thanks for deleting it. So any help guys? PLEASE! Helroz and Chainfire not working. What else to do? Is buying one of those codes on the net a reliable way of doing it? I dont want to buy one and then find that it doesnt work...

Mexico is nasty with this they often deliver the phone 'broken' (they do this on purpose) making unlocking pretty much impossible.
In Europe doing this is illegal but well in Mexico (latin america) it isn't. I have seen this with Claro in Peru also.
You can try with SRS software (unlocksamsungonline.com) but contact support first to tell about your problem.
Also I suggest removing the modded firmware because that has probably only made your problem worse. Put a non branded original firmware and check if your IMEI is still intact.

Check out this thread:
http://forum.samdroid.net/f70/repair-imei-s2-5729/
I can vouch for his service, used it before...

I will try the links posted. The weird thing is, that when i do the *#simlock# on the phone, it shows all the options in off, as if everything was unlocked. But when I put in a new sim it says sim lock! What can I do? Is it still worth buying an SRS account and trying to get it unlocked? I dont want to spend 14gbp and then have the thing not work... Any ideas? I have also reverted to original software now. I need more options >(

dertuman said:
I will try the links posted. The weird thing is, that when i do the *#simlock# on the phone, it shows all the options in off, as if everything was unlocked. But when I put in a new sim it says sim lock! What can I do? Is it still worth buying an SRS account and trying to get it unlocked? I dont want to spend 14gbp and then have the thing not work... Any ideas? I have also reverted to original software now. I need more options >(
Click to expand...
Click to collapse
you sure thats not a simpin not network lock? or the sim unlock pin was entered wrong now the sims blocked... got another sim to try?

Yeah ive tried other sims too, not working. ALL the locks show as off, but not working! I think the damn people just "broke" the phone and modify it so its impossible to unblock? I dont know what the hell im supposed to do... Tried almost every cable method out there, but not sure if to spend like 15 pounds more to get a code? I dont know if it will work... ANy other suggestions guys!?

dertuman said:
Yeah ive tried other sims too, not working. ALL the locks show as off, but not working! I think the damn people just "broke" the phone and modify it so its impossible to unblock? I dont know what the hell im supposed to do... Tried almost every cable method out there, but not sure if to spend like 15 pounds more to get a code? I dont know if it will work... ANy other suggestions guys!?
Click to expand...
Click to collapse
The thread I linked you two, he has a UST Pro II, it's a hardware unlock solution... Phone must be on GB or less, and rooted, he shares his UST's USB connection over network, and carries out the operation on your computer... Msg him explaining the situiation and see is a refund possible if it doesn't work...

Great topic mate!:good:

[Q] Demo note 2 imei and baseband problem

Hi i have been given a samsung galaxy note 2 but it is a demo from samsung. It has everything in it but it doesnt have an imei and doesnt register to a network. It has a sim slot but it doesnt pick up network. If i type *#06# it says imei null. Also another thing i noticed is that it has no baseband version. It keeps loading retail mode from samsung all the time however i have managed to get rid of it. Is there a way to flash it with different firmware to get sorted. I am not an expert so if someone can guide me step by step that will be great.

Hassanv2 said:
Hi i have been given a samsung galaxy note 2 but it is a demo from samsung. It has everything in it but it doesnt have an imei and doesnt register to a network. It has a sim slot but it doesnt pick up network. If i type *#06# it says imei null. Also another thing i noticed is that it has no baseband version. It keeps loading retail mode from samsung all the time however i have managed to get rid of it. Is there a way to flash it with different firmware to get sorted. I am not an expert so if someone can guide me step by step that will be great.
Click to expand...
Click to collapse
Return the phone and request a new one mate. Your story sounds fishy to me to be honest

gee2012 said:
Return the phone and request a new one mate. Your story sounds fishy to me to be honest
Click to expand...
Click to collapse
There's nothing fishy about his story. Samsung demo units only contain WiFi connectivity options to discourage theft and resale.
Sent from my GT-N7100 using XDA Premium HD app

Mister_Mxyzptlk said:
Ther to discourage theft and resale.
Click to expand...
Click to collapse
Which is exactly what this sounds like...
Sent from my quad core monster

One direct question, how the hell u got this phone or who gave it to u?
↖(^▽^)↗ Sent From Rego Galaxy Note!! ↖(^▽^)↗

Its not fishy it has been given to me by samsung for demo in mobile stores in uk. It does connect to wifi as someone mentioned its just it dont pick sim cards probably because samsung blocked it. As i got a sim with unlimited data i want to use it and get rid of my dongle and laptop.

Hassanv2 said:
Its not fishy....
...it has been given to me by samsung for demo in mobile stores in uk......
....I got a sim with unlimited data i want to use it and get rid of my dongle and laptop.....
Click to expand...
Click to collapse
Since samsung supplied it (in your words) for demo in mobile stores in uk I doubt they would be particularly pleased with it being supplied with an imei (which is TOTALLY dodgy to me) for personal use when it was never intended for that!
Sorry dude but it does sound fishy.

No manufacturer would be pleased to install custom roms too..... So solution please if you have any?

Hassanv2 said:
Hi i have been given a samsung galaxy note 2 but it is a demo from samsung. It has everything in it but it doesnt have an imei and doesnt register to a network. It has a sim slot but it doesnt pick up network. If i type *#06# it says imei null. Also another thing i noticed is that it has no baseband version. It keeps loading retail mode from samsung all the time however i have managed to get rid of it. Is there a way to flash it with different firmware to get sorted. I am not an expert so if someone can guide me step by step that will be great.
Click to expand...
Click to collapse
I would not flash anything if you have these issues right from the get go, take it back to place of purchase and or call your carrier. Demo is just that Demo...
Thank You and Thread Closed, before this goes into the woods....

Will a T999 with a Bad IMEI work outside U.S.?

Hi, someone is selling me a really nice T999 in excellent condition, with the problem that the IMEI was blocked, and it won't work on any carrier in the U.S. I live on Dominican Republic, will it work on my country fine? 3G and everything? I know that the 3G band matches the one my operator uses, so no problem there.
Thanks in advance.

djluis48 said:
Hi, someone is selling me a really nice T999 in excellent condition, with the problem that the IMEI was blocked, and it won't work on any carrier in the U.S. I live on Dominican Republic, will it work on my country fine? 3G and everything? I know that the 3G band matches the one my operator uses, so no problem there.
Thanks in advance.
Click to expand...
Click to collapse
ok use ordin and restore it http://forum.xda-developers.com/showthread.php?t=1949687

kiruba8 said:
ok use ordin and restore it http://forum.xda-developers.com/showthread.php?t=1949687
Click to expand...
Click to collapse
So you are saying that it will work without a problem?

kiruba8 said:
ok use ordin and restore it http://forum.xda-developers.com/showthread.php?t=1949687
Click to expand...
Click to collapse
You could have read more than the title and suggested something relevant to his question.
OP, I'm not actually 100% sure. But, I would imagine that you'd have no trouble using it.

Simple answer is yes.

Thanks for your answers. I ended up buying one on ebay that was cheaper, with the same problem. Only issue is that the auction says bad esn, but i guess that he got that wrong, and means imei. Here it is: http://www.ebay.com/itm/200888137396?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
Hope it turns out OK. I took a gamble with it.

djluis48 said:
Thanks for your answers. I ended up buying one on ebay that was cheaper, with the same problem. Only issue is that the auction says bad esn, but i guess that he got that wrong, and means imei. Here it is: http://www.ebay.com/itm/200888137396?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
Hope it turns out OK. I took a gamble with it.
Click to expand...
Click to collapse
Well, yeah, you really are taking one then. Because, IMEIs are for GSM phone and ESNs are for CDMA phones. That posting says T999 with a bad ESN... So, is it a T999 or a CDMA variant of the SIII???
Hope everything works out for you, bro.

Don_Perrignon said:
Well, yeah, you really are taking one then. Because, IMEIs are for GSM phone and ESNs are for CDMA phones. That posting says T999 with a bad ESN... So, is it a T999 or a CDMA variant of the SIII???
Hope everything works out for you, bro.
Click to expand...
Click to collapse
Yeah, i know bro. People tend to mistake IMEI with ESN, so hopefuly its one of those cases. If it isn't, i will have to return the phone.

How much did u pay..??
Sent from my SAMSUNG-SGH-I317 using xda app-developers app

sanchitgrover said:
How much did u pay..??
Sent from my SAMSUNG-SGH-I317 using xda app-developers app
Click to expand...
Click to collapse
USD$335.00
I think it was a nice deal if i get it to work here

djluis48 said:
USD$335.00
I think it was a nice deal if i get it to work here
Click to expand...
Click to collapse
let us know if it worked. I wanna buy outright and ship back home

x1tyme said:
let us know if it worked. I wanna buy outright and ship back home
Click to expand...
Click to collapse
Hi. Just to update. Just got the phone. It was indeed the T999 GSM. I got it to work here without a problem. Just remember to check that the 3G band your carrier uses its supported by the phone, otherwise, you wont have 3G.

djluis48 said:
Hi. Just to update. Just got the phone. It was indeed the T999 GSM. I got it to work here without a problem. Just remember to check that the 3G band your carrier uses its supported by the phone, otherwise, you wont have 3G.
Click to expand...
Click to collapse
nice to know. Will search for it and ship some back home with paying tax for it, of course.
Is ebay the source to buy bad imei?

djluis48 said:
Hi. Just to update. Just got the phone. It was indeed the T999 GSM. I got it to work here without a problem. Just remember to check that the 3G band your carrier uses its supported by the phone, otherwise, you wont have 3G.
Click to expand...
Click to collapse
Hello Luis.
I am considering buying a bad IMEI also for Honduras. Did you had to unlock the phone or something like that or just placed the SIM card and worked fine?

andrews317 said:
Hello Luis.
I am considering buying a bad IMEI also for Honduras. Did you had to unlock the phone or something like that or just placed the SIM card and worked fine?
Click to expand...
Click to collapse
Hi there.
Well, to tell you the truth, i sold the phone as soon as i got it because it wasn't compatible with my carrier's 3G network. I did unlock it, but unlocking was extremely easy, i just rooted the phone and downloaded an app from the Play Store, and the app did the rest of the work. Easy as pie. After that, the phone worked flawless in the small ampunt of time i spent with it (less than a day) and it was a brand new phone :highfive:. If you are wondering the name of the app, i don't know the exact name, but you can try searching "galaxy unlock" on the Play Store, and you will see a couple of apps. Good luck.

Almost same problem
djluis48 said:
USD$335.00
I think it was a nice deal if i get it to work here
Click to expand...
Click to collapse
Hey man I'm on the same situation than you, just That in this case its a nexus 4 and I also live in Dominican Republic. You got it to work? Hope you can help me out here bro

Randyjp said:
Hey man I'm on the same situation than you, just That in this case its a nexus 4 and I also live in Dominican Republic. You got it to work? Hope you can help me out here bro
Click to expand...
Click to collapse
I think that its going to be same, and that its going to work, because the imei was blocked on the country the phone was bought, it should work properly outside that country.

If you have a carrier phone with the IMEI blocked you can unlock it and use it on another carrier. Or you cant? I know u used to could. Also If you call your carrier. for instance tmobile and talk to a superviser they may unlock it for you... They usually do because you're using the phone with their network anyways.. So they still lose money if you decide to go to another carrier.

gypsy214 said:
If you have a carrier phone with the IMEI blocked you can unlock it and use it on another carrier. Or you cant? I know u used to could. Also If you call your carrier. for instance tmobile and talk to a superviser they may unlock it for you... They usually do because you're using the phone with their network anyways.. So they still lose money if you decide to go to another carrier.
Click to expand...
Click to collapse
If your IMEI is blacklisted then the phone has been reported lost or stolen. No US carrier will take a blacklisted phone. Tmobile and att share databases too.
Sent from my SGH-T999 using Tapatalk 4 Beta

EtherealRemnant said:
If your IMEI is blacklisted then the phone has been reported lost or stolen. No US carrier will take a blacklisted phone. Tmobile and att share databases too.
Sent from my SGH-T999 using Tapatalk 4 Beta
Click to expand...
Click to collapse
Not always.. Carriers will block the IMEI even you dont pay your bill for so long.. A friend of mine gave me his Sidekick 4G and he stopped paying tmobile. After a while that phone stop working. When I called tmobile they said it was because of the IMEI has been blocked. I said that I have this phone for a long time and you need to turn it back on.. 48 hours later they did

Samsung pay for Note 10+ not working

Hi all, purchased a Note 10+ for my wife to replace her Note 8. In short, Samsung pay used to work but when setting up everything for the Note 10+, its the only app i cant get working for her.
Says the phone doesnt support it. We are Aust based and i purchased from a Au seller. The website indicates its a AU/NZ model (SM-N975F).
I can get Google pay to work but not sure why i cant get Samsung pay to work.
Ive read about it begin region locked etc but as mentioned, the seller website indicated its a AU model. Also read that factory resetting may work but it was a new phone that i only just setup/restored data etc so dont really want to do all that again if theres no guarantee thats even a plausible answer.
I also read that when setting up the new phone, the simcard needed to be inserted from the very beginning which i did not do. I restored data via samsung switch first before transferring the sim/sd cards.
When i attempted to install an older Samsung pay apk, it goes 1 step further with the intro screens but then says connection issue, try again later.
I did search XDA but could not find any other threads that could help.
Anyone else in the same position with a simple fix that worked, thanks.

rexboy said:
Hi all, purchased a Note 10+ for my wife to replace her Note 8. In short, Samsung pay used to work but when setting up everything for the Note 10+, its the only app i cant get working for her.
Says the phone doesnt support it. We are Aust based and i purchased from a Au seller. The website indicates its a AU/NZ model (SM-N975F).
I can get Google pay to work but not sure why i cant get Samsung pay to work.
Ive read about it begin region locked etc but as mentioned, the seller website indicated its a AU model. Also read that factory resetting may work but it was a new phone that i only just setup/restored data etc so dont really want to do all that again if theres no guarantee thats even a plausible answer.
I also read that when setting up the new phone, the simcard needed to be inserted from the very beginning which i did not do. I restored data via samsung switch first before transferring the sim/sd cards.
When i attempted to install an older Samsung pay apk, it goes 1 step further with the intro screens but then says connection issue, try again later.
I did search XDA but could not find any other threads that could help.
Anyone else in the same position with a simple fix that worked, thanks.
Click to expand...
Click to collapse
I have a similar issue I have a N975W (Canadian) in the UK & can't seem to get SPay for my region, I'm stuck with the Canadian APK/firmware, with yous being a N975F seems it's region locked to Europe but with a Austrian CSC maybe?
In a nutshell until Samsung remove the region restriction for SPay (which they probably will never do) you're out of luck, sorry.

rexboy said:
Hi all, purchased a Note 10+ for my wife to replace her Note 8. In short, Samsung pay used to work but when setting up everything for the Note 10+, its the only app i cant get working for her.
Says the phone doesnt support it. We are Aust based and i purchased from a Au seller. The website indicates its a AU/NZ model (SM-N975F).
I can get Google pay to work but not sure why i cant get Samsung pay to work.
Ive read about it begin region locked etc but as mentioned, the seller website indicated its a AU model. Also read that factory resetting may work but it was a new phone that i only just setup/restored data etc so dont really want to do all that again if theres no guarantee thats even a plausible answer.
I also read that when setting up the new phone, the simcard needed to be inserted from the very beginning which i did not do. I restored data via samsung switch first before transferring the sim/sd cards.
When i attempted to install an older Samsung pay apk, it goes 1 step further with the intro screens but then says connection issue, try again later.
I did search XDA but could not find any other threads that could help.
Anyone else in the same position with a simple fix that worked, thanks.
Click to expand...
Click to collapse
Go to settings, about phone, software information.
Scroll down to where is says Service Provider.
What does it show?
Should be 1 of the following for an Australian model.
XSA/XSA/XSA
OPS/OPS/OPS
TEL/TEL/TEL
VAU/VAU/VAU
If it shows something else, that could be part of the issue.
The SM-N975F / DS are sold in a number of countries, with different csc codes.
The CSC I listed are for Australia, Samsung, Optus, Telstra & Voda.

Dolgogi said:
Go to settings, about phone, software information.
Scroll down to where is says Service Provider.
What does it show?
Should be 1 of the following for an Australian model.
XSA/XSA/XSA
OPS/OPS/OPS
TEL/TEL/TEL
VAU/VAU/VAU
If it shows something else, that could be part of the issue.
The SM-N975F / DS are sold in a number of countries, with different csc codes.
The CSC I listed are for Australia, Samsung, Optus, Telstra & Voda.
Click to expand...
Click to collapse
Cheers for the info. I just checked the phone and for Service provider it says the following:
SAOMC_SM-N975F_OXM_VNZ_QQ_0006
RF8MBOXOBCM
VNZ/VNZ/VNZ
It was purchased from Dicksmith online and they categorically advise its an Au/Nz model but appears not???

rexboy said:
Cheers for the info. I just checked the phone and for Service provider it says the following:
SAOMC_SM-N975F_OXM_VNZ_QQ_0006
RF8MBOXOBCM
VNZ/VNZ/VNZ
It was purchased from Dicksmith online and they categorically advise its an Au/Nz model but appears not???
Click to expand...
Click to collapse
VNZ is New Zealand

It's a New Zealand model, specifically it appears to be a Voda NZ model.
Either way, this is possibly why you can't use Samsung Pay.
Unfortunately, I'm not aware of a way around it.
Perhaps you can get it refunded since it doesn't fully work here?

TheInfiniteAndroid said:
VNZ is New Zealand
Click to expand...
Click to collapse
Cheers, appreciate the info. Ill have to clarify with the seller then on how they can promote it as an AU/NZ model when it appears it has to be either one or the other. If i had an AU model the CSC as you guys have pointed out would be right and i would not have issues with region based apps like Samsung pay.

rexboy said:
Cheers for the info. I just checked the phone and for Service provider it says the following:
SAOMC_SM-N975F_OXM_VNZ_QQ_0006
RF8MBOXOBCM
VNZ/VNZ/VNZ
It was purchased from Dicksmith online and they categorically advise its an Au/Nz model but appears not???
Click to expand...
Click to collapse
If it is Exynos you can try change CSC to your region and it should work.
Sent from my SM-N976B using Tapatalk

How do I change my CSC?

Zaileion said:
How do I change my CSC?
Click to expand...
Click to collapse
I followed all the directions I can find. Flash a different firmware. I tried New Zealand and still the CSC is MID (Iaq) which is what it was when i got it from Amazon. Its a 975f/ds which I bought specifically to be able to root it but this whole CSC thing is new to me since I haven't been in the rooting scene for 3 years which is when i gave up my beloved note 4 (best Samsung phone ever made by the way). Just trying to get samsung pay working so i can get it working on my samsung watch then i can flash all the awesome roms for my phone... any advice sure would be welcomed.

Dolgogi said:
Go to settings, about phone, software information.
Scroll down to where is says Service Provider.
What does it show?
Should be 1 of the following for an Australian model.
XSA/XSA/XSA
OPS/OPS/OPS
TEL/TEL/TEL
VAU/VAU/VAU
If it shows something else, that could be part of the issue.
The SM-N975F / DS are sold in a number of countries, with different csc codes.
The CSC I listed are for Australia, Samsung, Optus, Telstra & Voda.
Click to expand...
Click to collapse
So I am going to try to flash stock firmware for XSA and see If I cannot get Samsung Pay to work. Not that I will need it really since I'm going to root anyway but its fun. If I get it working, I'll report back.

I flashed the AUS Firmware and Samsung pay seems to work BUT... Grrr. It asks me to sign into my Samsung account. Done. Then it asks how to verify authentication it has a grayed out button to use fingerprint and a button to use pin, and a little spinning blue circle in the center of the screen and that is where it stays. Like its loading something but never loads. The use fingerprint button never lights up, and the use pin button isn't clickable. So close... Any ideas?

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.
Click to expand...
Click to collapse
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.
Click to expand...
Click to collapse
Check the card and make sure it's seated properly...

blackhawk said:
Check the card and make sure it's seated properly...
Click to expand...
Click to collapse
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.
Click to expand...
Click to collapse
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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Click to collapse
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.