Fnb can not help me!!!

My fnb credit card was in arrears & handed over to debt collectors, I have weekly debit orders going off on my standard bank account to try & pay it off. However, fnb keeps trying to deduct money from my fnb cheque account & when they can't, they deduct another R100 because there's no money in there for them to deduct. But why are they trying to deduct money from my fnb account when I am paying my debt off with the debt collectors??? & now my fnb cheque account is in arrears because they can't see that I am paying off my debt. Nobody at customer service can help me! This is ridiculous. They saying on their system they can't see the payments I'm making. So what am I supposed to do? Because I'm paying off my debt but fnb is putting me in more debt!!! Help please!!