Cartrack Device Cancellation

I'm currently have a tracker device installed from cartrack but I'm honestly not happy. Today I decided to cancel my contract with them due to poor service provided. One of their consultants by the name of Tebogo Seloga sent me an email with a cancellation form but on that form they requesting I pay R1700.00 for the cancellation. I'm failing to understand why should I pay them whilst the problem for the cancellation it is on their side. On the 22nd of April 2019 my vehicle was high jacked in Mamelodi East, I called them to report the issue and I spend about an hour with no feedback from them. I had to call them to find exactly of they could locate the car and they're feedback would be "we still busy trying to locate the car. Another hour I'd call them in the presence of police so we could hear where are they locating the vehicle so they can go to that vicinity to at least look for it and they'd refer me to another department where they'd answer me by " we still trying to locate the vehicle". This afternoon they called and they asked me what was the reason for my cancellation! I told them that I don't like their service while the consultant(Tebogo Seloga)tried to convince me not to cancel and they'll fix the device I asked him to locate where the car is at the present moment, he made me hold for almost 10mins and still came back with the same feedback "I can't locate your vehicle". So now why should I pay for tracking device which can't locate my car and they've been debiting from my account for almost 2 years. My query right now it is the R1700.00 they want me to pay for canceling the contract when I'm not happy with their service. That's not my fault that they've failed me as they're client. They've replaced 3 devices already but still don't find joy. They don't even call when I'm driving in high risk zones.