Cartrack **** artist

I installed a camera system I'm my truck , was working great , but sold the truck new owner wanted to take over system, but decided not to I ask for them to remove system, and place it in new truck , months went by where I kept asking about the unit, and even was told that unit wil be fitted on certain date, where I stop the truck and canceled all work for unit to be fitted, just to be to told units is not available at that time, so I stop paying for a service not rendered, after 4 months they told me they can fit a unit , but I have to pay 7 K plus , for a service I never received, I canceled my contract there and then , how can I pay for n service not rendered, no their lawyers are treating me , after all emails was sent to them of our mails back and forth, to get a unit fitted en new truck ... if you can avoid cartrack, they there for you're money even if there is no service