Welcome to iMore! We are a community of people passionate about Apple products and services but we have no direct affiliation with Apple itself. As far as I know there is no such thing as a "Genius product" or any type of free trial attached to it. The only service currently offered with a free trial is Apple Music. If this is what you're referring to follow the link for instructions on how to cancel your subscription. https://support.apple.com/en-us/HT204939