Pathetic customer service, No network coverage,

On the 16/07/2020 I had called in to cancel my contract due to the virus and job loss. I was told that I could not be transferred to a supervisor when asked to speak to one. I was told a supervisor would contact me between 2-24 hours and right until today no one has contacted me. I have called in today 25/02/2021 and they still cannot transfer me to a supervisor. We were guaranteed 10megs upload and 10megs download speed but instead we are getting upload speeds of 1.8megs and download 1.9megs and we are really determined to cancel now. Pointless paying for a service that does not work. The customer care email does not work and the MTN stores inform you to phone in to cancel and when you phone they cannot help you. What is the next step? This is costing me my time and my money and for what? MTN is the worst network in history.