Standard Bank's unnecessary debit order

I went to standard bank Mall of Africa branch to settle my revolving credit facility, the lady who assisted me was not very kind and she gave me attitude. I asked her if all is settled and I will not be debit end of mo th and she metioned that she did a manual close off on the account and I will not get debited.

To my surprise, I got debited this morning anf and i have no idea why because I have paid off everything, it is such an inconvenience when a highly regarded bank is so ineffecient in their service.

I want my money back.