Unauthorized Debit Orders

My cheque account is under siege with unauthorized debit orders of which every month I have to reverse on average 4. The bank seems not interested in giving this issue the urgency it deserves because they make R5 per transaction when you reverse and block. I have since lodged a case and i called their ***** line and they tell me its not ***** and i need to take it up with the debit order department. I'm extremely disappointed with how FNB is dealing with this issue. It is your responsibility to protect your clients from ********** activities and as such you need to act and give this issues the urgency they deserve....YOU MAKE THIS PROBLEM GO AWAY OR I WILL GO AWAY..............