MTN South Africa bad service

I had a 24 months contract and finished paying. They debt my account. All of a sudden after the 24 months contract. I get a statement in my email saying I will be charged a cancellation fee for early termination. I went to MTN shop and they told me they can't help and I should call MTN. I called them on the 10 of February 2026. They logged a ticket even the agent said they were not allowed to bill me since I paid everything and I'm done with my 24 months contract. On the 28th of February 2026 I get debit order from MTN. I can't reverse it because my bank says MTN has blocked it. MTN South Africa is a ****. Don't ever take a contract with them.