Paying for nothing

I have a Tracker installed to my car. At time of installation was told that system check if all is working every now and then and they will let me know. Got SMS 06/02/2014 that system is working. And not again. So phoned them and asked what is happening. This was 2 weeks ago. They said they will test and let me know. Got an email on Monday saying something is wrong they need to send a technician. Rep**** with detail when to contact me. Nothing happened till this (Friday). So phoned again. After 20 min call where they tell me it is my responsibility to make sure they test the unit. Not exactly the main problem. They are more than happy to take my subscription money but it has now taken 2 weeks and still no joy. If my car was ****** will it take them more than 2 weeks to find it? Was promised by the manager/supervisor at call centre that it will be sorted. Still waiting for feedback. At the moment I am thinking they are useless and if a car has to to be tracked it will not happen. I am livid.