Ensure that you have the newest versions of the extension installed, and LibFredo6 and the SketchUcation toolset [which manages licenses]. Restart SketchUp to sync everything. If you can't manage the licenses in the Tools submenu entry for the extension, then use the SketchUcation PluginStore page [logged in] item in its drop-down 'My Licenses', which should let you manage your licenses. If all of this fails text back and someone in support will try to help...