FNB credit card payment debit order not authorised for first of the month

Imagine my surprise when I see a debit order on my account for my credit card minimum payment on the first of the month. I have never authorised this. I do not want this debit order to go off on first of the month. I want this reverted to the arrangement I have had for as long as I have had the card. I want to make my credit card payment myself before the payment date. Make the change please. I tried calling the call Centre, held on for 30 minutes and then was cut off after 3 people could not help me.