Vodacom Contract - cannot be cancelled

I am unable to cancel my contract a year later I am still being debited. I spoke to the cancellations department on the 9 Feb 2024 and they promised they will cancel it however i have still been debited. They also told me they had no record of me calling in. Today I called *** cancellations, and it says I cant be helped because my cell number is now pre paid. 082135 Customer Care says high volume of calls and cuts me off. I had same issues over the year trying to cancel this contract and emailed customer care who acknowledged my email but now Vodacom says it was the wrong department and I cannot be refunded. I have all emails. Why is it impossible to cancel this contract? Vodacom should be brought to book for this ********* behaviour.