Unauthorized debit- insurance for a contract phone cancelled in 2020

MTN is debiting from my account for a contract phone that I cancelled in 2020. I went to the branch, the funny part is that when that contract phone I was with FNB. They started last month to debit from my ABSA account. Why would you wait 2021,2022,2023 and start debiting my account in 2024 when I don't even have a contract phone with your company! I DO NOT HAVE ANY PHONE CONTRACT WITH YOUR COMPANY!!!!! Actually whilst we are at it, I'll be cancelling the wifii contract that I have with you!