Bank charges keep going up,FNB won't stop activities on the account

Very bad experience, I've been trying to close my account without success now bank charges are up R4000, all I have been asking from them over 6 months now is for them to stop all activities on the account so that I can make arrangements to pay off the bank charges, they just can't help me, I guess they are waiting for them to get to R10 000 before they get help me, is that even fair, I mean how do you explain bank charges for R4000 I'm so sick of this bank and wouldn't advise anyone to move there, consultants are not helpful at all!!!!!!!