Here’s how to grab the Windows Update log files so that you can get to the bottom of the issue:
https://support.automox.com/help/how-to-retrieve-windows-update-log-files
Note that for Windows 10 and Server 2016 you’ll need to run the Get-WindowsUpdateLog cmdlet to generate the log file.
If there’s anything you find in the logs that you can’t decipher and fix, let us know and we’ll do our best to help.