When domains are registered, they are set to automatically renew by default. This setting can be changed by clicking the domain name of the appropriate domain in the Domain Control Center, and then clicking "Modify Renewal Preferences."
Unfortunately, renewals are not reversable, as per our terms of service and refund policies. There is no way for us to reverse them, and we incur a renewal fee for each domain, therefore there is no way for us to refund domain renewals.
Upon purchasing a domain, our system e-mails you a note indicating that the domain will be automatically renewed unless you set it not to do so. Also, before renewal, you are sent several messages 30, 15, and 7 days before renewal to warn you.
We suggest that if you do not want your domains to automatically renew, you go to the Domain Control Center and modify renewal preferences on all domains to prevent this.