Export glitch, multiple files auto select

When I select one photo to export and click the Export button, all previously exported files show up as, "The following files already exist." This is a new glitch for me.  Even after quitting and reloading Lightroom Classic, the problem is consistent.  Only one photo is selected for export.  I have checked this repeatedly.  Am I suddenly forgetting a step?  I can't hit "use unique names," or all the other files will actually duplicate too.