Frustrated with poor service

On the 30th of September I paid the full than on the 1st of October, MBD deducted an additional R500. The account is now in credit. I have called numerous times requesting a refund and a paid-up letter; to date, I’ve had no joy with my request. I’ve sent emails with the same request and once again no joy.

I’m frustrated because I don’t know who to turn to because all communication methods result in no resolution.

One agent I spoke with requested proof of payment, how do I need to send proof of payment if you can see the account is in credit, another agent said you don’t have the banking details to process the refund. How can you not have my banking details if you generated a debit order? You knew what account to deduct the money from just process the refund into the same account.

Please advise how I request a refund and a paid-up letter.