Horrible and worst service MTN Meadowdale

i returned my router and meadowdale in the beginning of September however till to date te month to month has not been cancelled worse i have been in contact with Shaun requesting for the contact ot be cancelled he never cancelled it he said i must contact 135, in September i was debited for the service and i still contacted MTN shop he denied the debit order i had to provide proof as now it was debiting in October however i had stopped the debit

This is affecting my credit score can you cancel this contract