Flagged eMail doesn't exist
I'm running Sonoma 14.1.1 (23B81) on MacBook Pro 16-inch, 2019.
Mail is showing that I have one eMail which is 'Flagged' but when I click on it, no eMails appear.
I've tried the 'usual' (rebuilding mailboxes, indexing the mail indices, producing a Smart Folder of eMails that are flagged, etc. but the 1 doesn't disappear.) to no avail.
Any thoughts?