Unauthorised Debit Order

I Had a Month to Month LTE Sim With DSL on the Telkom Network and have told the DSL Team Numerous times that im cancelling this sim since i mooved over to another Wifi provider and have not used the Telkom Sim every since , I even logged calls with DSL Team and Telkom on their webside for cancellation but yesterday i was billed from Telkom for service that i have not even use for more then 10 Months now

Reference: Eft Debit Order ***): Telkom (***S2605)