REFUND- OVERDEBIT

REFUND- OVERDEBIT I was over debited on my account on 30 March 2019 by an amount of R1414 more than my debit order amount. I called the call centre but was told the system was offline. I went into the EAST RAND MTN STORE and a ticket was logged. I was not contacted and am getting different versions of the turn around time. If I reverse the debit order than I look like a bad payer but if I wait for MTN to call me to return money that they have stole from me than I may never recover my money. I am getting the run around and am at my wits end.