Bring back fn+f2

[Bella_0910]

I press the fn+f2 the the screen turn black. Its sleep mode. And how to bring back the screen from the black screen?

 

[Ralston18]

Fn + F2 can also be a screen lock (e.g. Lenovo).

What make and model desktop or laptop?

Do you have the User Guide/Manual?

Unless there is some bug involved you should be able to identify key press pair to bring the computer out of sleep mode.

If sleep mode is really what is happening.