Billing issues money was not returned to bank account , but ATT climing they were, 3 weeks and no one can do anything about it

I have been on phone with ATT for 3 weeks straight trying to resolve the issue with billing, I paid my bill in time , than suddenly have got past due, paid that , payment showed as cancelled 2 days later, I paid again, posted  and 2 days cancelled again, paid again posted this time for good. Checking my bank and see all 3 payments were posted and nothing was cancelled and refunded. Att claiming they did refund 2 times!!!! i have phone calls records with them and chat transcript with them saying it went back to my bank account stating my debit card number. i have bank transcripts confirming there is no refunds. went to bank and filed dispute for those 2 transactions, money where refunded by bank , than after 1 week i wake up to past due balance on the amount of those 2 payments. Calling customer service, switching billing department and than supposedly supervisor!! nothing they can do because its Saturday!!! and ATT treating me to disconnect service if I don't pay immediately my past due, he offers me to extend that time and .... Surprise CAN NOT DO THAT!!! making claim and all i get number of claim no copy of it - i did repeatedly asking for copy to be send to me. A(Edited per community guidelines)OLUTELY ZERO SOLUTION!!!!! I HAVE BEEN FORCED TO PAY PAST DUE SO I WONT LOOSE PHONE SERVICE AND IM FILING LEGAL CLAIM ABOUT THIS (Edited per community guidelines)!!!!! IMPOSSIBLE TO GET ANYTHING OTHER THAN INDIAN ACCENT TALKING CUSTOMER SERVICE!!