Stop debiting for a cancelled service

ZERO STARS, if only that could be selected. Why do you keep billing me for a service that was cancelled more than 4 years ago ???????????? all you to is mess up peoples credit ratings and you run up our banking charges for your every once in a blue moon debit orders of R10 or R15 or R20. Can we please for once and all get this sorted......and can you please just stop charging me for a Telkom mobile service that was paid in full and cancelled years ago.