Cannot log into online account

I cannot access my online account for my business.  I have essentially been locked out since August of 2022.

Thankfully autopay still works, but as far as managing anything online I'm completely in the dark.

I have a business account with 10 wireless plans.  Somehow, when making a change on the phone to my account with phone support, they changed the primary account phone number to one of my other lines.

From that moment on I cannot access my account online.  Every time I try to login they prompt me to send a security code to the wrong device.

I went so far as to change the sim from the device they were sending it to to my own device and that worked for a day.  Then right back to sending the one time code to the wrong device.

This is a problem for multiple reasons.

1. AT&T is sending authorization codes to lines in the possession of persons other than myself.  Luckily I don't have trust issues otherwise this is a massive security problem.

2. Everytime  I try to solve this with phone support they give up and say they can't help me and I should talk to the technology support.  But, alas they transfer me and the process starts over from scratch with the next unqualified support person.

3. I should be able to override this text code to an email, or anything else.  It is after all MY account.

Any advice or perhaps a link to a proper support person who can help me out with this?