bank info on my account is not mine

Someone paid my bill last year, twice I think, without knowing.  It took me bit to figure out what was going on. 
The saved banking info on my online account is wrong..... and it won't let me delete it or update it.  I can choose to use " pay with a different account" option to input my bank info but cannot update, delete or add a payment account without getting an error. 
So today I called.... went from Customer service to technical service who had me call the billing dept. 
The billing department said they couldn't see a card associated with my account and asked me to refresh my screen.  So I refreshed the screen and the bank account information magically is now my bank account numbers.... so weird.. So I paid my bill and signed out and then signed back in to see if the problem was permanently fixed..... 
Sadly someone else's banking information is displayed again...... I hit refresh and it corrected again...
I guess I have a big issue with the fact that I could use someone else's bank account to pay this bill without their consent and if Directv can't explain how or why then it could also happen to me or someone else....