Compromised Safety (Installation of tracking device on a car that’s not yours)

My ex partner installed a tracking unit on my car and now when I tried to make contact with Netstar Customer Services to get the unit removed from my car I was told this can only be done with the authorisation of my ex partner because he is the account holder of the unit ON MY CAR! (a car that is in my name) I have made attempts to ask for assistance from different Netstar Customer Services consultants and nothing has been done from their side only “because they have a contract” with my ex partner ON MY CAR! My safety is compromised, I don’t even use my car anymore because I get called and harassed by this man because he has access to tracking my car. Why do car-tracking companies allow people to install tracking devices on cars that are not even theirs. So it means now people can ***** cars then install tracking devices on them because they know that no security checks are being done when you sign a car tracking contract to confirm if the car is yours. I am so disappointed in NETSTAR!