No sercice from Vodacom to cancel contract , since Nov and still strugling

In november 2033 vodacom called me for an upgrade on my existing contract only to find out in Dec 2022 that you actually didnt upgrade my contract you send me a new contract instead at an addition R800 per month. It took endless efforts to speak to your agebt to get it cancelled and returned, eventually end of Jan 2023 RAM collected the device and i though its the end of the terrible nightmare. End of Jan , my itemised billing is still showing the billing, end Feb 2023 still on my contract. Today i callled in to your cancellations department , still you cannot cancel the contract and the agent tells me it needs to escalated. Why was this not done in December 2022 when i called in the first time. I want you to please cancel this additional unwanted contract and you will refund me the monies paid over the period past collection. This is redicilous!!!!