Cartrack bad service

Service at cartrack its very poor.. Made an installation two month back I was only provide with a pink paper from their technician who did the installation. I made a query explaining how I was not happy with their devices but was ignore. Therefore this month debt order it's was dispute by me cause I was not happy. Only now that's when I received a call from them demanding payments. Never had a technician send to check what is the problem I have ALL they do is call and demand payment.. What happened to customer service and client being happy for what they pay for