Import no previews

When I click on import and then my SD card the screen is gray.  No previews load to select and import.  It worked fine yesterday and to my knowlendge nothing changed.  Doing the same thing to all my SD cards so I tried a different readed.  It's recognizing the card just no thumbnails to click on.  I also tried clicking on a folder on my desktop and it also won't load the preveiws.  I have normal preveiws is Library just no option to import.  I've restarted.  I checked and lightroom classic is up to date.  Any suggestions?  I am working on a Mac.  The images are jpg on my sd card and open fine in photoshop, just can't import to lightroom.