Debited for something I never agree on

I installed tracking device from cartrack..service was good. After tracker was installed I received a call to confirm it was installed and confirming banking details..then they explained about other products one was road side assist I said I have insurance that covers road side assist. End of the month I was debited for road side assist which I never agree on.Called cartrack to ask why was I debited for something I never agree.ask for the policy be cancelled and reverse my payment I was told they will charge me cancellation fee for something I never agree on it