Double debit order Unauthorised

African Bank debited my account twice on the same day toward my monthly instalment for a loan. But they took the normal instalment and then another Unauthorised amount of R735.90 from my account and that money was meant for my other debit orders. I tried contacting them with no success they are not responding to my mails nothing this is day 3 yet no feedback now what i must pay penalties on the other debit orders. I just need them to reverse the unauthorised amount they took from my account so i can pay my other bills. Pathetic customer service.