I had a bad experience with the Cartrack as some information was not explained to me correctly

I had a bad experience with the Cartrack as some information was not explained to me correctly.eg contract part I didn’t know that I took a contract of three years with Cartrack, I only learned about this information when I want to cancel after I sold my previous car so now I have to re-install the device with a fee ofcourse cos I didn’t have a full information