Go into the Settings App - Personalisation - LockScreen
Set Background to Picture and choose one
CLo9se the Settings App
Then open Windows File Explorer.
Paste this into the Address bar in File Explorer and press Enter, delete everything in the resulting folder
%USERPROFILE%/AppData\Local\Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\LocalState\Assets
Paste this into the Address bar in File Explorer and press Enter, delete everything in the resulting folder
%USERPROFILE%/AppData\Local\Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\Settings
Close File Explorer.
Then right click your Start Button, choose Powershell (admin)
Run (Copy and Paste) this command and press Enter
Get-AppxPackage -allusers *ContentDeliveryManager* | foreach {Add-AppxPackage "$($_.InstallLocation)\appxmanifest.xml" -DisableDevelopmentMode -register }
Restart (not shut down) your PC when thta command completes.
Go into the Settings App - Personalisation - LockScreen
Set Background back to Windows Spotlight, that wait a while to see if Windows Spotlight is working.