MTN billing me for a contract that has ended 7 months ago

I had a 2 year SIM only contract with MTN that started on the 19th February 2020 and ended on the 18th of February 2022, I have been trying to get my contract canceled since February with no luck.

Every week I call and talk to supervisors to have my contract canceled, but I am not winning. I sent emails to MTN complaints department They have never responded to my email. Every week it's a different excuse as to why they can't cancel my contract. I have over a 100 reference numbers from my escalations with MTN.

Instead of resolving this issue MTN has blocked my number.