Tracker does not honour their contract terms

I recently purchased a new vehicle and had a tracker unit installed. When I took out the new contract I was assured by the sales consultant that I could cancel my the contract on my old vehicle which was in the process of being sold. He explicitly indicated that Tracker will allow this because I am taking out a new contract. Now Tracker wants to charge me for the remainder of the contract on the old vehicle that I do not own anymore. This is completely ********* and I advise anyone looking for tracking services not to use Tracker due to their ********* behaviour