You have sold your listing, congrats! Now you just need to mark it as sold to prevent more potential buyers from contacting you. Simply login to your dashboard, click the listing that sold and click "Mark as sold." You'll be presented with the names of leads that contacted you. Click the person that you sold the home to as the purchaser.
If your listing on the site is a model, you're listing will remain active even after you mark the home as sold.