FNB - Charging fees they should not.

FNB deducted an amount for a debit order for a personal loan. I called to ask that they stop this debit order as the account was fully paid up and reverse the unpaid item charge. I was told that the debit order will be stopped but they will not pay me back the unpaid debit order fee. I am now 36 minutes on the phone being bounced off one person to another.