Harassment

I had tracker device with Cartrack company into my vehicle, and it happened that i sold the car. I spoke to the new owner of the car to continue with cartrack device and he agreed, I decided to call Cartrack for them on helping the new owner of the Vehicle to continue with their Tracker Device and it was successful done and completed. I'm so flabbergasted and furious to get texts messages from Cartrack stating that my account is in Arrears with different amounts every months.