Refund

How do i get my refund. I made payment arrangements for July 25th 2018 but, I paid online early on the 23rd. I called and gave the rep and gave info. I was told no money would be deducted off my card. I went to store on 25 to make a purchase. I couldn't because my account was in the negative. I have talked to 7 different people in 2 days plus the card company. I was told by several AT&T employees it would take about 24hrs, 2 employees told me 2 hours. It's Friday now. No refund has been made, my account is still in the negative. When i call AT&T now, they put me on the hold and never come back to the phone. I was going to cancel service in April but, I was talked to staying with a bundle deal of about $86 a month. I still have to call every month because i'm being charged over $100 a month. Can someone please tell me how i can go about to get my refund