Sleep button not working for keyboard shortcuts

[nebyelats]

I'm new to linux lite (and linux in general), so I don't know much. I was trying to configure the sleep button on my laptop to put the monitor to sleep like it does in windows, but it doesn't work and I'm not sure what the issue is. Under keyboard settings / application hotkeys, I put the command "xset dpms force off" and tied it to the sleep button, but nothing happens when it's pressed. When configured to other keys, the command works as intended. I can verify the sleep button itself works and is recognized by the OS.