CANCELLED MTN CONTRACT but still being charged

I have been harassed and invoiced for services not rendered since July 2025. I had the MTN home Wi-Fi and returned the device to MTN Pinecrest Mall in Pinetown, Dbn in the 1st week of July 2025. I was then debited R2500 for the device which I reversed. I've gone to MTN Pavilion, Dbn and the Pinetown branches and was assured it was now over and done with. I called MTN on 10th March 2026 to give my 30days notice for my mobile data contract and was told the other home wifi contract is still active. Now, a few minutes ago, I got sent some kind of Trace notice and I needed to accept acknowledgment of debt! I owe this damn network nothing! Never dealing with MTN ever again!