I'm a Car Track customer currently running a fleet of 14 cars

I'm a Car Track customer currently running a fleet of 14 cars. Last week Monday I recently had a new unit installed in my car. The next day It happened that the unit or the connection was faulty by giving false power off alerts everytime I start the engine. I had reported this problem for more than 5 times but till to date no technician has been dispatched and the repairs dept insist that I pay R600 repair cost meanwhile the unit is new. This is really a disgusting & poor service.Can rather take my money somewhere else where I will be treated with dignity.