False Duplicate Errors

I am using LR6 on Windows 10.  i7, 32GB, 4TB of SSD.

I am adding JPGs to my library.  When I add them, they do not show as greyed out as if they already existed.  When I hit the add photos button, it gives me a dialog that says "Some photos were not added.  Duplicate items.).  

These are not duplicate.  I have searched my library for that name and nothing exists.  I rename the files, adding a unique prefix (prefix-orginalname.jpg) and I get the same behavior.  It is not just doing this on a couple of files, it is doing it on all the files in the import batch (about 30).  

I have tried files from different folders and keep getting the same error.  I have restarted LR and get the same behavior.  

I assume duplicate check is name, date and file size. So if I changed the name, if it was a duplicate, it would then import.

Here is a loom of me getting the error.  https://www.loom.com/share/f454ca5be0e94ad6aa50044d19621897