There’s a bug that can cause work loss. It’s easy to check if you’re affected. It involves naming and/or renaming a document and might only be triggered if iCloud is used. As far as I can tell, the bug occurs in the latest iOS/iPadOS and Pages app. I’m running earlier software versions so I’m unable to test.
There’s discussion at MacRumors…post #8 has a demonstration video:
https://forums.macrumors.com/threads/pages-the-document-was-deleted-in-another-location.2257974/
For those who depend upon the app for their workflow, a workaround I saw mentioned at Apple Support Communities––after naming or renaming a document, save it. Don’t enter any text to the doc body before doing so. Thereafter, as long as the doc isn’t renamed, work is supposedly safe (to the extent it normally is).
Test and use extra care, or avoid till fixed.