Number disconnected without notice

Same boat. Many are being told this happened because their phone is not compatible with the network (VoLTE compatible). My phone is compatible and I confirmed with them a year ago but they still disconnected my account with zero notice. It is impossibly frustrating and now we have to try to interact with these people without a working phone. I wish you the best of luck!

I think it's not the phone, it's the plan, but the paygonline website access to manage the account and change plans has been disconnected along with the number.

I also tried to link my old number to the new att.com page but got the message "That information doesn't look quite right. Try again."

The main issue is how to recover the old phone number.

Website access to upgrade plans or to get a new phone with the old number has been locked.

Changing carriers is another option but that would entail getting a new phone number.

I'm having the same issue today. I prepaid for a year, still have over 6 months remaining. Tried to login today to see why my mobile network isn't working only to see my account has been disconnected. If it's about the phone type like you're saying above I was given no notice. Tried the AT&T chat but it's just a useless bot. I can't phone in to customer service right now because my phone is disconnected. Right now I have a Huawei P30, if I get a new phone and they don't reinstate my remaining paid months I'm switching providers. 

ATT's official information, with a link to the list of supported devices

https://www.att.com/support/article/wireless/KM1324171

It says that if your device is not on the list, the device (not the number) will stop working, and that it's possible to switch the SIM card to a new, compatible device.

Even if my phone was not compatible (which it is), my SIM card would still be operational and ready to insert into a new device.

However, my number and SIM has been disconnected, I lost my phone number and current balance.

@Rayherself I won't pretend to be an expert on any of this. 

Unfortunately, as far as I understand it, the US government has blocked Huawei devices period. 

On any carrier. 

We're happy to help with information on our AT&T Prepaid changes and options if your device was a part of the 3G phase out @GaryGaryGary77.

Yes. Since we shut down the 3G network, there won't be data or voice service for devices that don’t have at least have 4G capabilities. This means that while some device features might still work, you won’t be able to access our network unless you upgrade to a newer device. 

Please ensure you are checking your specific model number to see if it matches:

• Will my AT&T phone work after the 3G sunset? - Be sure to check the specific model number
• Wondering if your unlocked non-AT&T devices will work with AT&T?-Be sure to check the specific model number
• How do I prepare if my phone isn’t supported? Shop our current deals to upgrade your device to a phone that is compatible with our network. 
• Curious about your current phones capabilities? Review your device, some require software updates to enable HD voice, Wi-Fi Calling, Video Call, Advanced Messaging or 5G
• Does this affect PREPAID? Talk and data services will only work for AT&T PREPAID wireless phones and devices that support at least 4G LTE and HD Voice.

You can find additional information to these questions and learn more by visiting our 3G sunset article.

Important Note:

• Some overseas models may not work with AT&T's network. This is a hardware limitation for the device. 
• We no longer activate phones that don’t support HD Voice as they won’t be compatible to work on our network when 3G shuts down. 
• If you switch your SIM card between devices, make sure the device you’re moving your SIM card to will work on our network.
• if you want to use your original device again, don’t forget to make sure the SIM from the original device will work on our network.

Customers still using 3G devices will most likely also be contacted via Email and Text message with more information. You can also visit your local AT&T Store or Contact Us if you have questions about upgrading.

Alasani, AT&T Community Specialist 

@Nicolas81 there are Huawei devices on the AT&T list of tested and approved supported devices, just not the one I have. I've been using a Huawei in America for over a year with no issue until this 3G phase out. 

@Rayherself I appreciate your response. 

Again, that was as far as I understood it. 

However, if the device you have is not on the whitelist... At&t won't allow it to work on the network 

Doesn't necessarily mean that it can't... but just that they are not going to allow it to  

The workaround I'm using... for an international phone.. Samsung Galaxy A70... also not on the whitelist... and that is currently fully functional with the network... involves making sure the IMEI number that At&t system sees is one it deems compatible. 

I had to get a new SIM card and transfer my account (prepaid) to it... with a IMEI that the system recognized (in other words,  not the one from my actual phone).