Faulty tracker units & bad service

Terrible service , I have 4 vehicles fitted with tracker units 2 of the vehicle trackers are faulty I can not track movements of my business cars ,

When I called tracker Port Elizabeth I was told a complaint had been generated and a technician would get back to me ,

2 weeks later no call received , I called again they asked who did I speak to , how am I suppose to know the person I spoke to over the phone?

After that they dropped, I tried calling again they do not answer now,

I have been paying tracker for the longest of time , all my premiums are up to date , and yet I’m paying for faulty units,

I’m really not impressed with the service received