A NIGHTMARE to cancel my contract!!!!!! Cell C pathetic service

I'm struggling to cancel my cell c contract!! My contract ended in March 2023 and I've tried on multiple occasions since April 2023 to cancel the contract. Whenever I call to cancel my contract the call agent assure me that it has been canceled but I keep on getting debited and receiving calls to say I owe cell C and my contract was never canceled. This is really pathetic services. The calls are suppose to be recorded and there they will find I've asked for a cancelation MULTIPLE times!!! I don't know what to do because whenever I phone to canceled it I'm assured it will be canceled but it never has.