Disappointed former client

I took out a contract with the above mentioned company in 2021 October and we had a good relationship between a (consumer) which it was me in this instance and service provider(Cartrack) until 2022 September going forward. In 2023 June my car had a mechanical failure and I took it to a machenic and the entire engine was dismantled completely and that was done over a period of four months and sadly during this period I never received any form of communication from Cartrack. That's when I started reversing their debit order because I felt I was not getting value for my money. I started getting threatening messages that they will blacklist me and I sent them couple of emails informing them that I no longer have a Car and they said I owe them R1400 including cancellation fee but two days later I got a phone call from them saying I owe them R2400 including cancelation fee... I am very disappointed by the company that I trusted so