very bad service

I have 2 accounts with African bank. one of my account was debited on September without my concern. I kept receiving calls from African regarding my account, and I kept on asking who gave the authority to debit my account, I was promised to be given a call back but with not success, sometimes when I am busy would ask them to give me a call back with an answer to advised about that debit till today. now they went and debited R700 plus in my account without my authority. that is ***** in so many levels, I want my money back and I still need clarity of who gave the authority to debit. how will I feed my kids nthe whole of December and January. now I have headaches non stop because of this, I made arrangement for one of my account and wanted to do the same for this one but how do I if the company was not able to give me answers. I used my time and money to call all the numbers I got from the consulted but still I have no luck, worse they can only pick up one of the account, now I have to pay internet café to send this. Its CLEAR that my information is not protected at all .I am gonna open a ***** case against this company