tracker does not deliver its services to me

dear sir /mudum my name is Zacharia Masolane phali,stays at 544019 zone 3 sebokeng,in march 2015,i called tracker to test a signal on my car, a opel corsa 1.4 bd52bkgp.they said the unit does not respond,and they will send a technician to my place to fix the unit.i have been calling tracker every month until july,2015 there is still no one coming out to check the unit in my car,i feel that my life is not safe in case of highjacking.no one will know where I am.i am paying services every month but my life is at risk,i have no more hope or trust in tracker(confused)m