Just to add some more information on notes that can’t be deletedL
I had two duplicate notes in my Inbox that were forwarded from gmail to my Evernote address (As usual, the app logged out, I thought i lost the note I originally sent so i re-sent it and then it re-appeared in my inbox so I had 2 copies).
Initially when i tried to delete one of the duplicate copies, the “Delete note” option was grayed out. After i moved one of the copies to another notebook, closed the app and re-opened, i was able to delete the remaining copy.