I have never had this issue before. My understanding is that on the MacOS (and Windows app) all notes are stored locally and synced to the servers.
Now, when I disconnect from the Internet and work remotely without Wi-Fi I can no longer edit notes I have open or create new notes, etc.
Attached is the message I see.
I have tried signing out and signing back in, restarting the computer and restarting Evernote App.