tracker account

Before joining trackersa with my first vehicle, I was told by tracker that I can buy a tracker unit, get it placed in my vehicle and that if I ever need to remove my unit and place it in another car it can be done. I then bought a tracker unit for the car and also paid monthly fee to tracker. I have recently bought another vehicle and phoned them to tell that i would like my tracker unit removed from my previous car as i bought the unit and want it placed in the new car, now tracker says that units cannot be removed from the other car and placed into the new vehicle because they cannot remove it without possibly damaging it and that I must buy a new tracker unit and place a new one in the new car. tracker then put another tracker in the new car and now they are charging me for both the tracker in the old and new vehicle. i am very upset about this because i wouldn't have bought the unit for the 1st vehicle as it is a waste of my money as tracker **** that unit can be taken out and put in other vehicles.