I am unable to move photos into an album in Photo
I'm using OS X 10.10.5. I downloaded four photos from my iPhone. I am unable to move these photos from "Last Import" into one specific album that already exist, but could move them into other albums. It seems to be just one album that is "not accepting" ... I can move the same photos into any other album.
Thoughts? Thanks
OS X Yosemite (10.10.4)