I am having the same problem as kpgkpg. After my Mac booted, command-space did not bring up Spotlight. I checked the Keyboard shortcut and it looked correct. However, I changed command-space to command-L to see what would happen and it worked - command-L bought up Spotlight. So I changed it back to command-space and to my surprise, it worked. I don't know what is going on but this is what I'm doing now - if command-space does not open Spotlight, I bring it up using the microphone key (I am using a Keychron keyboard). I only have to do this once, and then command-space works all day until I power down the computer. Thanks!