Unlocked S7 Galaxy has no Enhanced LTE setting visible, cannot make calls

The only S7 that works according to AT&T is their branded version. 

Does yours start up with the AT&T boot screen?

How old is the SIM card.

https://www.att.com/support/article/wireless/KM1062165/

Mine does not start with at&t logo, it starts with samsung. Can the phone be programmed to be at&t branded?

I have an unlocked Samsung Galaxy S9+ and it is acting the same.  Called customer service from my work phone and she tried all she knew but nothing fixed it. I restarted multiple times, even tried safe mode, nothing changes.  I got a new sim card. The rep used my phone to make a call and it worked.  Got to the parking lot and tried to make calls but can't. Went back in the store and he said there's nothing else I can try. Spoke to another customer who has an unlocked galaxy S10 and he said he had to get a new phone.

Hey, Laneman25! We see you have questions about your unlocked Samsung Galaxy S7 compatibility with AT&T's network. We're here to help!

As our ACE mentioned, AT&T's branded Samsung Galaxy S7 (G930A) is the only version compatible with AT&T services. The only way to convert over from a Samsung branded device to a AT&T branded phone will be to purchase one that's AT&T branded. Compare the model you have with the one on the list of supported devices. This may be the reason why you're unable to use the voice feature. Also, if you're using an old SIM, replace it which requires a Nano Sim. We hope this helps! Please let us know if you have additional questions. 

Thank you for reaching out to AT&T Community Forums! 

Jonye, AT&T Community Specialist   

This ATTHelp comment does not check out. My device is on the list, I have correct SIM, but it does not make/receive calls. Feel free to check my help ticket number: 2264987714. I was told today that my S7 G930A is End of Life. I suspect this is a software issue and it just makes more sense [for them] to have us buy a new device.

One background note: I bought the phone when I had AT&T as carrier. Then I switched to cricket.

Get this. I first tried the usual troubleshooting measures but then decided to factory reset. Before I did this, I had the option of enabling "Enhanced LTE Services." This of course was enabled but calls didn't work. After the factory reset this option disappeared.

I also tried Samsung support. I started with the text support. It ended with me sending my device in for repair but I had to call the support number to get that organized. I called with the ticket number and everything was confirmed but she hung up on me at the very end of the call. I didn't know what to do and assumed a package would arrive to send my phone in since she had gathered all my contact details. Nothing received, no calls or email. I called again and provided the ticket number. This time they say the S7 is End of Life and that it will not be accepted into repair center.

I wonder what song and dance I will get if I call again: why didn't the first and second rep catch that my device is End of Life? Or is the third rep incorrect?

Why is my model on "the list" but not working?

@Timmay531 

Is the S7 running the most current software (for its model)?   AT&T Androids often do not get software updates if they are on a different service provider.  Even though At&t owns Cricket, that might be the problem. 

https://www.att.com/device-support/index/Samsung/SamsungG930A/

It would not be the only At&t branded phone that doesn't work.  Age is not a determining factor, there are 1 and 2 year old Samsung flagships, and at least one iPhone 13 that have the same problem. 

Att really 🤬 this up

@formerlyknownas Is this a device manufacturer issue? The phone hardware is there, just that the firmware has to be updated to work with the carrier's hardware? If it's not clear, I don't have a firm grasp on all of this.

Thank you for the link. My device has Android 7 and an ancient baseband version apparently. Which is frustrating because "Software Update" is highlighted and has a blue exclamation mark, but running it yields "Software up to date." Other than pressing "Software Update" I don't know how to update. From your link, the "Troubleshoot & Resolve to fix software update issues" was not helpful but I had high hopes. Would an AT&T rep loan me a SIM to try and run updates while in the store?

Before I hit buy [on a Google phone] I might learn what xda-developers have to say about ROMs now that I have a brick. Can I skip baseband versions to the most recent available for my device or do I have to incrementally update?

That's a good point about updates I had not considered or knew about before switching to the discount, yet wholly owned carrier.

@Timmay531

Yikes.  Way out of date.

AT&T phones frequently don't get updates unless connected to AT&T directly, as a service provider.  Those updates were critical to its function with HD voice. It should be running Android 8.

If you are have a PC and a feel handy, flash the updates. You might find a Samsung repair center that can Flash the updates. The problem is those updates are 4 years old and may not be available any longer.  

@Timmay531 i feel pretty confident that you can flash the correct firmware yourself via odin. not super fast and the firmware is a HUGE file... but definitely doable.

the question is... is it worth it? my previous phone is an S7 (still have it). use an unlocked S10 now (don't get me started on what a (Edited per community guidelines) it was to get than thing on ATT VOLTE).

point being, my S7 was getting super slow. and honestly, that FREE S22 promotion ATT has going on is a pretty solid deal.

obviously, there's caveats... like you pay the tax up front, then each month, you are billed like $22 for the phone, then ATT refunds you the $22 on the next bill... or something like that. and you gotta do this little "song and dance" for 36 months. you are technically not on a contract, but you kinda are at the same time. because if you bail on ATT before the 36 months, you have to pay the difference on what you owe.

BUT if are gonna stick with ATT for a while, it's a pretty solid deal. i didn't do it because i didn't want to commit for 36 months, i was already (Edited per community guidelines) at ATT for my S10 issues and i'd honestly rather the have the S10 (no plastic, curved screen, glass back, SD card slot and most importantly, a HEADPHONE JACK).

just something to think about though.

@formerlyknownas Yes I feel handy yet inexperienced. If you have any knowledge base links with readmes to share I would appreciate it. Thank you for your responses and support through all of this. I really expected a dead thread here.

@Dumbfoundeder That's a neat app but did not work. I dled the Ray W. version, followed your steps, and received "Error: Hidden network settings activity not found on device." Thank you for the idea.

@centaurus3200 For me it is worth it. I like to fix things and buy used gear whenever possible. I got this device new and never broke the screen or had any other issues; I take care of my things. If the device is technically capable of working it just boggles my mind that the companies can't/won't help. I also want to consume less and so I challenge myself to seek solutions. I don't find the phone too slow but after the apple story of them intentionally slowing phones down...I mean christ everything is justified if it turns a profit.