Cell C let me down

My phone was ****** on 28 November 2019. I tried to do a sim swop once I got a new phone and sim card. I was assured the sim swop was done but I cpuld not use my number. After 3 attempts the sim swop was done but I still could not use my number. I called the contact centre numerous times and have done everything the agents told me to do but still after 6 weeks I cannot use my number. In the mean time I still get billed for my contract. After losing hope I informed them I'm cancelling my contract with immediate effect. They sent me a letter telling me I have to pay a penalty fee to cancel my contract early and I have to give them 2 months' notice. They don't even bother to try and sort out my problem! Very poor service. I had this contract for 17 years and this is how much my loyalty means to them. Cell C number in question: ***.