Poor customer service

Took a laptop on 36months contract, when laptop arrived via Ram couriers the screen was cracked called them back immidiately and took back the laptop they said they are cancelling my contract and i will apply for another one after 3months. From october 2021 till now i am being debited monthly for a laptop i have never used. Everytime when i call i find a new person and ask to speak to their manager or the person who was assisting they say they don't know a cindy,byron,nelisiwe or sphiwe. I am also being debited for life cover that they said they cancelling back in october with the contract.