Unreliable tracker, easily jammed, no back up device

Bad experience ever. I want to cancel my remaining 2 tracker contracts. My car got highjacked in December 2019, Cartrack failed to recover the car. Even worse, the tracker was jammed within 10 minutes. They don't have a back up device incase the is a tracker jamming. Till today, I've never received a call from them for an update about the ****** car, I don't even know if the case was closed or what. I was even the one calling them for an update always, they never bothered. The tracker of one of the remaining cars, it not functioning properly. All of this shows how unreliable Cartrack is. Why do you pay for tracker that is easily jammed with no back up? I'm not happy with Cartrack at all. Just want to cancel my contracts, thats it. I'm so disappointed and hurt.