Vodacom won't cancel my contract!

I have had the worst possible experience with vodacom. I took out a cellphone contract with them in Jan 2019. A month before my contract came to an end I contacted the call centre to inform them that I did not want to continue with the service provider and that I wanted to be moved to prepaid. Regardless of my multiple attempts to cancel this contract I am just getting nowhere. I have been paying for a service I do not want and have canceled telephonically since December 2020. This is starting to become abusive to say the least and pure theft! Everytime I complain or ask to speak to a manager or complaints department I get told that due to Covid that is not possible. When I threaten to take them to the ombudsman the consultants simply put the phone down. I am at my wits end! I will never recommend this service provider. Pathetic service and poor client engagement on all levels.