Hello, thank you for reaching out to Microsoft Q&A.
Method 1
Click Windows + R key, type
%USERPROFILE%/AppData\Local\Packages\Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy\Settings
You will see two files there, (Settings.dat and roaming.lock)
Rename them to Settings.dat.bak and roaming.lock.bat
and restart your computer.
Method 2.
Re-register the Spotlight feature.
Click Windows + X key, open Terminal (Admin).
Run the command below and click Enter.
Get-AppxPackage -Name Microsoft.Windows.ContentDeliveryManager | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml" -Verbose}
Once completed, restart your computer.
Method 3.
If the above two steps do not resolve the issue, you can use a small third-party utility called the 'Dynamic theme' app from the Microsoft Store and install it on your device.
https://apps.microsoft.com/detail/9nblggh1zbkw
See if the Spotlight feature works normally.
Let me know if you still need more help.