Once again money taken by them for their errors

Nedbank requested that I cancel my debit order for my credit card with them and transfer funds instead as they couldn't find a reason that my debit order kept returning when there was sufficient funds. Only to now realise that due to their errors I am being charged each time I do the transfer on my cheque and credit card. These charges clearly means nothing to them as all they do is pile up bank charges and you get nothing in return