Changes to file lost

[Steve van Ommen]

I was editing a Word file in Onedrive, saving as I went - then the screen froze. I saved a copy to my desktop assuming I could at least save a copy that reflected most of the changes I had made.
Neither the desktop copy nor the Onedrive copy retained the changes ( remember I had been saving as I went)

Wondering why? Is there a way to recover them?