Insurance that never been canceled with the cellphone contract

Horrible isn't the word of service I had a contract with MTN that has been canceled on the 18th of October 2022 after several months of calling to cancel my contract. I spoke with Karobo of Management Team on the 18th Oct and he told me that my account has been passed on to the Mtn account and I owe Mtn nothing. Only to find out a week ago that I still owe the insurance an outstanding amount that I need to pay ,I don't even know for what, even if I'm not a customer of MTN I still need to pay. On the day I took out the contract the salesperson told me once your contract expired the insurance will also be canceled because the insurance is included with the cellphone contract. This is really terrible of MTN, I won't recommend them to anyone!!!!!! Poorest service ever