Tracker caused damage to our bakkie

Got a Cartrack tracker installed in my Isuzu KB250 about 2 years ago when they left my engine light was on we contacted them and they sent out an auto electrician to look he said there were too many trackers in our bakkie and removed 2 trackers from our bakkie did a reset on the bakkie and the engine light was off since then we have just gotten problems with our bakkie we have had to replace batteries,starters,sensors and much more we have a major electrical problem with our bakkie we contacted Cartrack stating they must stop our tracker because of the damages they have caused they keep phoning is saying that we owe them money and are going to hand us over to the debt collection agency after we had told them they caused us damages to our vehicle and we do not want to continue using their services