Hi mcleanb1, I'm assuming that you are using a pc and the Chrome browser. If so, this might help. Just a note, I've "lost" folders and bookmarks too.
Click the 3 vertical dots above the other bookmarks-- go down to Bookmarks -- Open the Bookmarks Manager--- Under the Folders column, open and inspect folders for the "lost" item. DON'T RUSH.. If and when you find that item, move it to where it belongs. added** it will more than likely be the last item in a folder **
Hope this helps. Good Luck,
edited - 9/28 to add ** bj