removal of a tracking unit

On the 24th October, I have made a review regarding moving of a tracking device from one car to the other, and i was promised that it will be sorted out till today Nothing has happened except for the harra*****t of getting calls and emails that I owe Tracker, which is very false because I paid for removing and reinstalling, so I need my money back and I no longer need your services because you can't locate the car with your own device given that after telling me to pay for removal and reinstallation, which was $900 and something, you still want me to pay to locate the car so am saving tracker the trouble I no longer need their services plus the car is sold so why pay for what I don't owe