My Tracker Failing their clients

From the 22/02/218 I received an alert that my tracker detector is not working, immediately I call my tracker to find out what's the problem. They confirmed that my detector is not working, I log a call for technician to come out from them to resolve it, they promised that Monday the 26/2/218 technician will call to come And resolved the matter as I was still in Cape Town hence we arranged for Monday. Monday no one called Tue the 27/02 I called to make a follow up, again they promised someone will call. With no lucky Thur the 01/03 I called and was not even having hope on them saying if they can't resolve the matter they must cancel my tracker with them. Surprisingly they said will have to pay R1600 for cancellation. That I don't have such amount of money to waste I said they must speed up the matter it's not safe to pay Tracker system that is not working. They again promised someone will call me, up to today the 3/03/2018 no one contacted me. This My tracker is so useless and they don't see to the needs of their clients. Now I'm sitting with tracker system that I'm paying for of which is not working, what will happen if my car could be taken how would I track it yet I pay tracker every month? I'm so angry with this really coz I'm at risk at the end of the day and I'm the one who will lose.