OneNote notebook reverted back to an older version

I was unable to edit a section of my notebook (on the desktop client) so I opened it up in OneNote online. I clicked "Edit in OneNote" and the application opened up showing me the entire section, now editable.

However, all my other sections reverted back to old versions (essentially the versions of when I first made the section, thus empty.) How do I go about fixing this? I've tried going to my "backups" but for the most part those are pretty outdated as well. Any help on this is highly appreciated.

Best,

Mauricio