Unit faulty since day one , and cartrack seems not to care

I have been having a problem with cartrack's tracking device from the first month after installation. Yes I reported it and someone came to fix it and guess what it's been faulty again ever since! I've been calling to get it fixed with no luck, I called in the other day last week spoke to the customer service manager who promised he'll call me back he needs to escalate it and guess what, it's a week now still waiting for the call and my unit is still not working, will cartrack replace my car if it gets ******, since they have been debiting my account but the unit they gave me has not been working since God knows for how long. Been calling the scheduling department, all they do is give me wrong times and wrong information, the incompetency in that department is shocking! I have asked to cancel the contract and they told me I'll have to pay the remainder of the months of the contract, which I'm not happy about because the unit in my car has been faulty ever since. Cartrack will pay for my car if something happens to it. I can't be running after you guys all the time whereas you are very quick to debit my account but the tracking device hasn't been working from the first month