MTN no service, (Poor service)

I have an MTN contract for probably more than 15 years, there used to be good reception at my place of work, but for about 2 years the reception quality has decreased to a point where I have no reception. When I wanted to cancel my contract by hook or *****, I was caught in a 3-year contract (maybe I missed some small detail). So, I had to endure the pain, not knowing it was going to get worse. I contacted the MTN Call centre on the 28 of July 2020 to do the cancelation and shortly after the call received a SMS stating the MTN have taken notice of the cancelation. To My surprise on the 14th of August MTN phoned me for a upgrade. I once again called MTN and a very nice gent attempted to assist me. He informed me that the person that handled the cancelation on day one did not complete some step and he then mailed here to arrange for the cancelation to be completed. On The 24 August I sent MTN a mail and got an email with a reference number stating I would get a response with in 8 hours. Here I am 9 days later no response. This type of attitude is why I want to cancel my contract, Shame on you MTN. ENQUIRY REFERENCE NUMBER ***