Unable to close my account

Firstly I am promised call backs but no one is calling. Also was quoted R400 to cancel my contract and my account was debited with R570. Have made numerous call to different people to have a technician to come in to disconnect the tracker device and no such luck. Service here is pathetic. So disappointed. My new insurance company advised me to not put in a new tracker device as it will drain the battery power. I have been driving the past month without a tracker service. If I am hijacked will Tracker take responsibility?