TELKOM BILLING ME FOR THE AMOUNT I PAID

I made payment on the My Telkom APP.I just got a sms saying my account has a out standing amount R1176.19. I called the custome service.gave all the information.but they are saying the payment is not showing on there side. On my account the amount was debited. TELKOM BILL PAYMENT 457896*0698 07SEP *** When to the to get a prof of payment.They said because the payment was made on the My TELKOM APP.They printed out a statement showing the money went off.I SENT IT TO TELKOM EXPLAINED WHAT THE BANK SAID.And THEY are telling me the BANK STATEMENT IS NOT ALLOWED...WANT TO KNOW WHAT IS THE WAY FORWARD NOW.

The only reason I charged, was because they debit my account on a wroung date.THEY send a wrong invoce.With he amount they have to debit.