When you have users that have Errors syncing file using the latest OD4B client.
It might be that there are some special characters like # and %.
That are in the file name, and are not supported by default.
Connect to the SharePoint Online Management Shell Using PowerShell.
These commands require version 16.0.6323.1200 of the SharePoint Online Management Shell or greater.
Run this command to see the current status
When you see NoPreference, you need to run this command.
Set-SPOTenant -SpecialCharactersStateInFileFolderNames Allowed
Keep in mind that it will about 2 hours or more before it gets active ….
If it still does not work you can run this procedure to force it :
If OneDrive sync seems to be stuck for a long time and nothing else is working, try a reset.
Be aware that resetting OneDrive re-syncs all your OneDrive files, which could take some time depending on how many files you’re syncing.
Press WinKey + R
In the Run window, enter: %localappdata%\Microsoft\OneDrive\onedrive.exe /reset
After reset the OneDrive, files with special characters (# %) were synced properly.
PS : See here for more info