Cartrack service sucks

Firstly let me say how disgusted i am with car tracks service after being a client for over 4 years, I had an attempted hi jacking, I pressed and pressed my panic button with no answer when I managed to escape i called them and the technicians response was they haven't received a signal for 2 months and my unit was faulty.

I asked for the unit to be fixed and waited 3 weeks with no response then I reversed the debit order and got a response back from them asking for their money but my unit hasn't been fixed, I cancelled the service and they still demanded there money for a faulty unit.

No I've been listed as a bad payer when i told them they can have 10 cents a month.