Bad aftersale service reveived

On Monday, a tracking device was installed in my car by netstar, I was happy and over the moon. Two days after the installation, we noticed that the device is draining my battery, I called in and reported and the response that came back was that they are fully booked, they can only fix my car after 9 days, meaning I will not be able to use my car till then. What a bad service, they do not take it as an emergency, yet they have my money already, stating that they will squeeze me in if there is a cancelation... Mcm, wish I can just cancel and leave them with those fully booked clients coz I bought a car to use not to look at it and decorate using it. Now I know, they won't take priority in trying to recover my car if anything can happen.