How many bytes is the backup? Did you save the backup to a synced folder? (A folder such as Dropbox, Or maybe My Documents when synced to Microsoft Cloud)
Answering these questions won’t fix your problem, but I wanted to see what might have caused them and how this might be prevented in the future
As a pure speculation, this backup might have been happening at the exact moment when the computer went to sleep. Even larger speculation that interrupted backup process might have corrupted the profile but at this point it's looks like "wishful" thinking and too many coincidences.
It might be interesting to test this hypothesis though. Many programs are rarely tested in such destructive fashion (at least by their developers). Moreover, such tests are very hard to simulate and automate.