FNB credit card bouncing back each month. Account in arrears nobody wants to assits me.

Worst service ever. I phoned and emailed them several times to stop my FNB credit card debit order on my Standard Bank Cheque card, then they tell me it's stopped and what happens this morning? Still bouncing back! It's been bouncing like that from April month until now. My standard bank fees are sky high because of this debit order that keeps bouncing every month for 2/3 times a month. I will pay off my credit card at FNB and never use them again.