To refresh your Sold comments, go to Inventory > Refresh Sold Comments.  Click the Sold Comments tab.  This will take you to a page where you can click the blue button to Refresh All Sold Comments.  Be aware you are limited to clicking this button only once per hour.  It may take some time for the system to work with the Facebook system to scan your albums and retrieve the Sold comments.  Wait and then refresh your page to see which items have retrieved sold comments for.  Leave this page open, and open your manage inventory page in a separate window or tab.  Locate the items and mark them as "Sold Outside Pop" or mark them as appropriate for the comment received.