Dext Prepare collects items from your DropBox folder automatically every 6 hours.
The most likely reason for items not being collected is that the link to DropBox has broken - this could be because your Dropbox folders have been renamed, moved or shared with other people.
In this case, disconnect from your DropBox and then re-connect.
If this does not work and your items haven't been collected longer than 6 hours please contact our HelpDesk team and we'll be happy to help you out.