Frustrated customer

Telkom is debiting my account after my contract is closed. A month after I cancelled my contract I am still getting debited for something I dnt have and a different amount is getting debited, your signal is pathetic &, so is your service. Cannot explain why R119 is debited on 25th where as my contract was R150 debited on last day of the month. This is very frustrating for me to be keep calling telkom and they don't know why and can't can't see anythinf on my account as for it so closed, so if its closed how the HELL is the debit going off??