Now that DirecTV and ATT are separate... how can I fix my acct to not go through ATT anymore?

I have been with ATT/DirecTV for at least 15 years now. 

I have not had anything ATT-related in 6 years, only DirecTV.

It has been (Edited per community guidelines) dealing with both ATT & DirecTV, and even after they have separated... our billing still comes from ATT despite hubby and I calling MULTIPLE times trying to explain that we only have DTV and don't want to be associated with ATT anymore.

Has anyone gone thru this? Can anyone provide some help? There are some AMEX deals I want to take part in that I cannot do b/c I am billed under ATT. But like I said, we have not had any ATT services since we bought our house 6 years ago. And we have told the ppl on phone help this!

I will message DirecTV for help also, but starting here hoping maybe they will see it and DM me. 

Thanks!