If the Google Drive not syncing or stuck or the files or folders are missing somehow, restart the Google Drive app could be the best fix.
Go to the path C:\Program Files\Google\Drive\googledrivesync.exe and then double-click the googledrivesync.exe file to open Google Drive for Desktop, and it will sync all files that missed automatically.

https://sites.google.com/view/gooogle-drive-not-syncing/home