********** DEBIT ORDER NOT PROVISION FOR

I have a cheque account *** with Nedbank and i did not provision any debit order to go through on this account and to my surprise, i was debited with R1273.26 and when i inquired this debit order at the branch i was advised that it is part payment for account: ***20 1. i have requested them to update the banking details for the account that they should the repayment from however it was not done and on top of that they went and debit unauthorized amount from the account which is not meant for debit orders. That amount must be refund and they should debit the correct account number provided