I saw that another person had a similar issue as I do, but mine goes a bit further. I use Bridge to cull my images and then I drag the final images over to LR. Once there, I typically tag them and edit as normal. However, that past several times I have done this, many of the images that I try to drag over are not able to be imported. LR says This Photo Is Already In The Catalog. Some images I am able to import, but some are greyed out. (And not greyed out like I can check it, but even more greyed out like it's unavailable) These images have never been imported into LR, and this is the first attempt to do so. I have tried to uncheck the Don't Import Suspected Duplicates, but nothing happens. What's going on? Please help! (Here's a screenshot in case it helps.) Thank you!
Which version of Lightroom are you using?
Please expand the "Destination" panel in Import window and change the destination to a new folder.
Try out the steps mentioned in this comment linked Re: lightroom thinks my pictures are duplicates
Let us know if that's helpful.