Bad Service

I sold my car. Contacted cartrack day after. They advise that I need to pay R850 for removal and refit of old tracker. I said its fine. They took the money through a debit order. 3 weeks down the line. The car is not with the garge I sold it to. They sold it already. As per cartrack I have 5 days after the car was sold to report this. I did. Now they are keeping me liable for paying for a new device. I did as I was ask to. They have delayed the process from theor side now I am being punished. This is not fair!