Problem with Lightroom Classic 5.7.1 recognizing previously uploaded pictures.

LR is not showing a large number of pictures I previously imported into it.  As an example I have a folder on my G hard drive  called Betty which has 66 pictures in it.  When I look at Betty in Lightroom folders it is only showing 35 pcictures.  When I try to import, and select the source "Betty" all 66 are displayed but they are all greyed out, so the 31 missing pictures can't be imported into the catalog.  When I hover over one of the pictures, it says "This photo has already been imported". or "This photo appears to be a duplicate of another photo already in the catalog".  I tried to Synch the folder, and there was no impact, the problem still remains.  This is a relatively new issue.  I used to be able to see all the pictures that I have stored on my hard drive in Lightroom.  Should I re-install Lightroom?  If I do will all the tags like keywords, and attributes be saved? Any other ideas?