You may cancel your membership within 14 days of purchase to receive a refund. You can also just turn cancel your plan at any time so that your membership expires at the end of your annual commitment, and not automatically renew. To do so, simply log into your account and look for "Membership Details". Then find the "Cancel Plan" button near your active membership.
For assistance on canceling a membership, or closing an account completely, please contact Customer Service through this form.