Tracker Device Stop Working 2015

Hi I bought my car in 2012 the first tracker Unit was installed and it stopped working and was replaced in 2014. After the installation of the new unit it stopped working in 2015. I have been paying for a unit that is not working since 2015 till now i want my money back because even now the device is not working and i am driving the car. I want to stop the my new contract with them because they are not trusted because when i talk to them they lie. They lie like their bosses when i ask them for the report they lie and when asking for my refund they tell me is not me is separate department. I wish to tell South African not to trust Tracker SA they lie to people and i hold for hours on the line to talk to them. Even this month will continue to pay for working device that is not working. Now i want to talk to their CEO to deal with lairs that are in his company. Everyday i get attitude and wrong answers from Call Center people. I asked them if my car is ****** now who will pay they said is not us. I asked them for gun to guard my car they refused. Lairs lairs from TRACKER SA