FNB greatly disappoints

Good Day, After transferring the required amount to pay my credit card on the 15 November, FNB still went ahead and deducted an amount from my cheque account (I am a premier client at FNB) on the 16 November, which appeared like an unauthorized transaction on my account, reflecting another card number, which appeared ********** to me. When I called the premier banker at FNB, who had to call me back, after her investigation, stated that this was a debit order, and I had to correct her, in saying that it is not, and then she went on to say that it is an autopayment when the required fee to pay one's credit card has not been done. This was not the case, I did pay my credit card well on time?! She couldn't do the reversal today, and said I should call back tomorrow to arrange the reversal myself??!! I am sorry, but that is not the kind of service I expect from a bank who states "How can we help you"!!!!!!!!! I have been a loyal client for over 13 years, and this is totally unacceptable.