Poor service., bad attitude

I joined altec on 2013 in witbank branch.they install the tracker and said I must come after six month 2 check if tracker is stil working. They said they can't check ciz their phones are not working. THey gave the numbers that I can call and confirm if de tracking device is still working and they gave me wrong numbers.in de begining I called them to check for me where de car has parked . They said I must first start de car and called them they can tell me where dat car.so was angry and stop paying them due to poor service. Now they are busy calling me and threatening me dat person is so rude he said I owe them nd if I don't pay them he said he will take me yo they lawyers. M so disappointed with altech netstar reference for dat cal is ***