Terrible service

I have had my tracker unit in my vehicle for almost 3 years, I was told that the unit will self test and I will receive an sms every six months to inform me if my unit is working or not working, I have not received one single sms in the 3 years they don't even call to say there might be a problem with the unit until I actually call them and report I have not received an sms then it takes them 3 weeks to come back to me. I then requested an upgrade to their most advanced unit skytrax with wich they inform me I will have to pay R400 to do the upgrade when they advertise that their installation on all units is free, how does this work?? they would be getting more money monthly out of this but they don't seem to worry about that