MTN is the worst cellular service provider!!!

If I could give them zero stars, I would. My contract with MTN ended at the end of June 2020. I called them on the 15th of June to find out what I need to do to cancel the contract. They said I can only call them once the contract is over. So I tried calling them on July 1, 2020. No answer. Sent emails. No answer. Sent Facebook messages with a reply that they will get back to me. They still deducted their monthly premiums but we reversed the debit orders for September and October. Now my number is completely unavailable, despite requesting that my number should be placed on a prepaid option. I have had this number for more than 15 years and all my contacts has this number. How can they just completely deactivate my number without my permission??? Absolute worst service provider when it comes to trying to cancel your contract. DO NOT trust them.