Good Sam travel assistant insurance.

When I bought my travel trailer from camping world the the finance lady sold me on the travel assistance insurance. Ok I took it and signed the contract. Tell me how many people read these insurance policies at the time of purchase. Any way, I read every thing when I got home and to me that insurance does not do any more than my own insurance, and I don't want to spend an extra $695.00 which was added into my contract with the credit union. So I read in the insurance contract that the membership is subject to cancellation by either party at anytime for any reason. So I want to cancel it. It says by written notification. I called the finance lady twice but no call back. Need some advise on how to proceed please. Thank you

Steven