I have the same issue after the most recent update. It's been telling me I don't have permission to one of my notebooks that I use every single day. Please let us know how to fix this.
Update: I was able to do this today in macOS Catalina.
Open Evernote > click in Evernote > select "View" on the top menu bar > Dark Mode > select "Light Mode"
Evernote will be back in "light mode" #blindedbythelight