Vodacom *****sters!!!

I've worked abroad since January 2022. In June 2022 I contacted Vodacom to downgrade my contract to sim only. I received no invoices via email since then. I assumed everything was in order. Since then the cell number in question has been disabled and no active products appear on my vodacom profile. I'm still getting billed for a cell phone contract that doesnt exist. Vodacom customer care departments have also been useless trying to help and eventually directed me to the legal department who directed me to the debt collectors. The cell number has been disabled for years now, no invoices, no active contract on my profile (confirmed by vodacom customer care). Every now and again I manage to stop the debit via the bank, then it starts again. The legal department confirmed today that my contract is still active!!! No mention of amount outstanding or any other 'contract' details. How can you hand someone over to debt collectors without informing them about the amount that is outstanding. How is this legal and not outright *****??? I literally can't contact Vodacom to cancel a contract that doesn't exist!