The images you see on the lock screen are downloaded from the Internet. You can go through the list of solutions mentioned below and get your Windows Spotlight not working issue fixed.
The common reasons to experience issues with Spotlight are corrupt image or system files, problems with device drivers, and outdated Windows update. Perform a System Restore 16 Solutions for Windows Spotlight Not Working Issue Remove Mail and Calendar from Lock Screen Re-register Windows Spotlight using PowerShell
Stop and Restart Windows 10 Spotlight Feature