MTN Appalling Service!!!

I had a 3 months contract with MTN from January 2019 until January 2022. I called customer service in at the beginning of February 2022 to cancel and they confirmed that it has been cancelled however the account is still active and I am owing according to my credit record. I've been calling customer service and MTN Pavillion and I've been transferred to different departments and no one is able to assist me. When I'm asking for a paid up letter no one seems to know where I'm supposed to get if from. I'm very disappointed by this appalling service and I don't want anything to do with them ever again.