Bad service

I am a happy customer,BUT when they say something and then do the complete opposite I am not a happy customer.July my debit order did not go off as usually and I paid the amount into Cell C's account.I called customer service and the guy I talked to assured me that there will not be a penalty fee.But heaven be hold!There was,so I am not happy with the service.If thy say there won't be a penalty fee,then there should not be one right?