Cartracker bad service and ******* practices

I was a good customer of cartrac paying 250 p/m for my one car. I called them for an explanation why am I paying more than other ppl do why is that on TV is R130 and I am paying roughly R260 for the past 3yrs. The lady told me I'm paying because I have a contract with them that's it she couldn't break it down to explain the services I'm paying for. I traded in my car I called for cancelation of the contract since I do not own that car anymore I bought a new car under my wife's name and installed another Trac from car track they are still deducting money 3months after I have called to cancel now I'm paying two car trackers acc for only one carnhave called numerous time no assistance. I reversed the last month debit order they are sending me emails and messages threatening to take a Ligal action against me and take my name to credit bureau. Last month the debited again now I didn't reverse it I left it. I do not know what to do I feel like I'm being robed by a big company with a team of lawyers that even if I can take them to court I will lose more money. I have called them and email them now I'm tired all they want from me is money. The last guy I called way Ivan baloyi who promiswd to call me 3 weeks back he hasn't Im still waiting paying for services I am not enjoying. The other lady I called told me the contact was canceled but money is still being debited from my acc.