MTN blocked my phone because I ended my contract with them after 3 years

I've been with MTN for years but this is the first time they treat me this bad. I took out a cellphone contract 3 years ago and I called it confirm cancelation. I was offered other upgrade deals which I gladly declined, this was on the 12th July 2025. The contract I'm on is for a phone and sim card but ever since I informed MTN that I'm not renewing my contract, they blacklisted my phone. They took their last debit order but my phone constantly has no signal, it's been a week of me calling and they take from pillar to post because they keep insisting that there is nothing with the phone. They deliberately blocked it to co**** me into changing my mind. This phone has been great to me. MTN really now?