Hours of edits disappeared! How can I retrieve them?

Last night as I finished 7 hours of major edits on a form, I navigated from the logic map back to the form questions and they had reverted back to the version from the day before. All work disappeared. I had been conscious to save each logic window as I completed work on it throughout the day. All new questions and associated logic are gone. And all edits on questions and header pages are also gone.

When I click on “Version History”, it is blank.

I submitted a help ticket on Typeform, but wondering if anyone can suggest a way to access my work?