Tracker is *********** its customers

I decided to take up tracker in 2017 with my previous car. I changed cars last year July and I was told that in order to cancel tracker as my insurance offered their own tracker, I had to pay R1, 800 because I had 3 year contract with them. I decided not to cancel this as I did not have R1,800 laying around so I had to pay R217 monthly. I have now changed insurances so I will not be using the insurance companies tracker. So I decided to I will call tracker to install a new tracker in my car and continue with my tracker repayments. However, I was told that I would need to pay R1,200 to have the new tracker installed in my car as the contract was in the previous cars details not the new car. I have been paying R217 monthly, I am simply changing car details, I do not understand why I need to pay R1,200?