Irrational Behaviour

So I am leaving the country and had to terminate my contact early. I have two cars at R800 per car so R1 600 plus my normal subscription of R 453 for December. As Murphy would have it, it turns out the unit in my one car is defective and which means if my car gets ****** or family kidnapped then it will be untraceable. I reported the defective unit and tracker said due to me cancelling the subscription that now the warranty is void and I need to pay R 500 for a technician to come out. My contract is valid till 31 December and thus I feel Tracker needs to cover this cost.