Returned debit order charges, high charges to block debit orders

FnB caters for the rich and notvthe average south african . R105 FOR A RETURNED DEBIT ORDER. R80 IF YOU WANT TO CANCEL A DEBIT ORDER INTERNALLY ON YOUR OWN ACC WITH THEM THAT THEY BILL YOU MONTHLY FOR. I am currently un employed and have notified my life insurance funeral policies here of so that they can stop debiting my acc. But because I know how sloppy our service providers can be I requested the FNB who I am a client of to block the debit orders on their side. They notified me that it costs R80 per debit order to be blocked on my acc with them that they charge monthly fees for. MY acc is in a minus of R1300 in favour of FNB because now I'm paying R105 per debit orders that was returned. I cannot close the acc because it's in a minus. I cannot prevent debit orders because I don't have money to pay R80 per debit order. FNB now only caters for big earners not the average or unemployed South African. I didn't choose wisely