Cartrack refuses to remove device.

So today I found out the car I bought 2 years ago has a Cartrack Tracker installed. Neither I nor the dealership I bought the car from knew about the tracker and no doubt it was a forced install by some insurance company... The tracker is now draining my car battery. The best part is, the previous owner never cancelled the the tracker and has been paying for the past 2 years! Now I need the tracker removed from my car so BMW can sort out the battery problem. Cartrack is however refusing to send out a technician to remove the tracker as they cannot locate the previous owner of the car to confirm that it has indeed been sold and before they can contact him I am stuck. As if a ******** will take in a vehicle to a dealer and actually contact them to remove the tracker? I am now carless as the dealership does not have courtesy cars. BMW is doing everything on their behalf to assist me in this process which I am thankful for but I could have had my car back by now if Cartrack was not so strubborn! I wasted 200 minutes of call time on them, only spoke about 15 minutes - the rest I was put on hold! I have been promised call backs all day but received none, no names to work with and no reference as proof that I am being helped or that the problem is receiving attention...