Contract still not cancelled

I cancelled my policy on 24/11/2023 with Vodacom and I was told the last debit order will be in December as it is a months notice. But they still charged me for January. That number is not even active since 24/11/2023. I was told they would email me the cancellation paperwork in December and I still have not received any paperwork and they are still deducting MY money. Never take out a contract with vodacom .......