Move and copy are grayed out, only add is available
I am trying to import pictures from one external drive to the main external drive where I store pictures. The copy and move options are grayed out. Both LR and the macOS

The only reason that I can think of is that the drive I'm trying to copy the files to has ~20GB of free space while the drive that I'm trying to copy the files from has about ~50GB of files but the import will only copy ~8GB of files.

