Being harassed for a contract that was cancelled

The worse people to take a tracker out with,over a year ago I sold my car and told them to cancel the tracker because I don't have a other car they told me I need to pay a cancellation fee that I wasn't aware of when I took the tracker with them, i asked them many of times where is the recording that's I agreed to all this, they couldn't provide me with the recording were I agreed on things that I wasn't aware of , now they keep harassing me and my fiance and keep debiting our accounts were that is fruad I told them to cancel my tracker because i don't have the car the next time they call or debit my account I going to take legal action against the company for putting me and my fiance through alot of stress and for being harassed