can not delete photos from photos

How are you trying to delete?

It will depend on the view you are using.

• If you want to delete photos from Moments, years, selection, select the photos and press the "delete" key ⌫
• If you want to delete photos from Albums or Smart albums, select the photos and press the command ⌘ and the "delete" key ⌫ at the same time.

Don't forget to shw the "recently deleted" album with "File > Show Recently Deleted" and to empty the album.