unauthorised debit-carebox

I recently got an sms advising me that a debit of r99 was taken out of my account ref care box. I have not authorised or approved any debits from my account and I find it extremely disappointing when a bank takes out debits without any discussion with the account holder.i pay my monthly account fee and I don't expect my account being debited for any other amount unless I have signed for such debit to be deducted.i feel ****** of money that is mine.i expect my money back! I will also be closing my account because if unauthorised money leaves my account then clearly my money is not safe with fnb. Seriously annoyed and disappointed.