VODACOM Complaint - cancellation of debit order after contract expired

My contact with Vodacom expired on 26/02/2021 but Vodacom kept on debitng my account monthly to date. Even increased the monthly bill. I have tried unsuccessfully to cancel the monthly debit order, cancel the expired contract, migrate to prepaid. Visited the Vodacom stores. Called the hotline. Talked to Toby. Phoned numerous times. Been told numerous time that I will receive a sms to confirm, and that an agent will call.

How to get out of this and why is it so difficult to cancel an already expired contract and relevant debit order with Vodacom?