I have the same issue, Evernote 10.67.4. Note title appears fine in all views I can find except right-clicking, "Note Info" reveals there is no Title ("Untitled"). Export has "Untitled Note" exactly as @tavor said.
I do recall there used to be an option to auto-title or use the first line of the note as the title. My memory is not what it used to be.
I am currently importing my ~4k notes into legacy V6 to see if exporting from that resolves the issue.