Contract ended complain

I would like to complain about Mweb as my 2-year LTE contract ended this year in January 2025, and they are still deducting from my account without requesting consent and I have not used their sim card ever since y contract with them ended. They are now threatening to blacklist me over payment, and I have not renewed my contract with them. I am really not happy and will not recommend anyone to use them again.