Mobile Sync Shows a Phantom File--How to Remove?

For the last several weeks Lightroom on my desktop has shown that a single image is still syncing with my mobile app. I have tried to figure out what the image is, but when I go to the Preferences panel and look at it there is no Asset Path/Link shown. All it shows me is under Sync Details/Errors, where I can see a file name that indicates it should be on my iPhone, but when I go to the iPhone there is no image with that file name. Is there a way just to remove this from the sync panel so that it can move on to other things? (Not that there are other files to be sync'ed, just it's annoying to keep seeing "Syncing 1 Photo" in the top left of my screen all the time.)