My unit is not working CARTRACK said they won't send a technician for repairs

My cartrack main unit is not working it has been on the same location for over 5 days and i have been calling them daily but they tell me it is a GPS and they can't send a technician for that they have reset network and GPS for over 10 times the issues has not been resolved

Today i called them again but the consultant were rude to me when i told the i want to cancel their service after again they told me they wont send a technician for my issues they said i must pay R5800 for the unit that is not working