Bad telkom service

I signed a contract with telkom and they disconnected my router I went to telkom cradlestone mall and the consultant said the debit order didn't go bcos of insufficient funds....so I went to the bank for a bank statement and gave it to the consultant ...and he said now hes not sure as to why the debit order bounce....cos the is money in the account he will tell the head office to call n resolve the matter ...I'm still waiting till now I'm tired of going to the store cos I dont get any help ...only to find out that when I opened the contract they captured wrong banking details n still didnt pick that up until I asked them to check and now they add the charges on my account and that was their fault to start with so y should I pay for their negligence....tell me?