you could enable spotlight desktop wallpapers on Windows 11 from controls -> Personalization and then Lock screen.
Ensure that the Background option is set to Windows spotlight.
A Few users report Windows Spotlight Image Not Changing after Windows 11 upgrade.
Check your internet connection
Windows Spotlight requires an internet connection to download and display new images.
And the first thing you gotta ensure have a stable and active internet connection.
Resetting the Windows Spotlight prefs can help resolve any underlying configuration issues.
Again a random bug or a glitch might sometime cause the spotlight feature not working on Windows 11.
Re-register Spotlight Using PowerShell
Sometimes spotlight feature not working issue can be triggered by a potential inconsistency.
If the above solutions didnt fix the problem, make a run at re-register the Spotlight using PowerShell.
Windows 11 Spotlight not working issue could be triggered by system file corruptions.
FAQ:
How can I enable Spotlight in Windows 11?
Why is Spotlight not showing on the lock screen in Windows 11?
Can I manually change the Spotlight image in Windows 11?
Why is Spotlight stuck on the same image?
Why are the Spotlight images blurry or low resolution?
Can I disable Spotlight in Windows 11?
Lets Optimize it