AT&T / Thunderbird review: AT&T servers not recognizing my information

Up until 4:30pm today (4/21/22) my email client (Thunderbird) was working just fine. At 4:37pm, I received a notice that AT&T was temporarily suspending my user ID (for my "security") and I could either verify online, call the 800 number or reset my password. Since I was at work (I don't own that computer), I opted to reset my password. I received verification from AT&T that this was done. I got home around 6pm to find that my Thunderbird email (I have used this for over 15 years) would not load due to "server error" from AT&T... not recognizing my user ID. I went in and deleted/reset email password with Thunderbird only to get the same message stating that neither the incoming or outgoing server at AT&T would recognize my information. I then spent almost 2 hours on the phone with AT&T Customer Service (most of which was dead air due to the 'agent' not saying anything). Suggesting I go to the T&T Resolve website does nothing for the problem I have which, according to Thunderbird, needs to be resolved with my 'provider'... AT&T. I asked for a manager or a 2nd tier tech to speak to with absolutely NO luck. I admit I only speak English but the agent had a hard time with even that. Most of what he said I couldn't understand due to his heavy accent. That, coupled with the lack of help or willingness on his part to get an answer, made this one of the WORST Customer Service calls I have EVER had with AT&T in the 15 or so years I have been paying them monthly (both wireless phone and U-Verse). MOST of the time, the service is good, people are helpful and things get straightened out quickly when needed. This time, however,... not so much! Until the problem is resolved, my main email and all of the stored information I have there (contacts, emails, etc.) are not accessible which will make life a great deal more annoying than usual! NOT GOOD!