Sleep function playing up!

[Eddie]

I have my Mac set to 'allow power button to put the computer to sleep'.
This was working fine but now when I press the 'on/off' button it doesn't go fully to sleep.
Instead I can still see the arrow and have to press 'enter' a few times before it responds.

Frustrating!

Why is this happening?

 

[Kaveman]

I don't use the power switch for this, using a mechanical switch all the time is just asking for costly long term repairs, especially when there are ways to do it with software.
You may have damaged your power switch.

Apple Menu > Sleep

Or in System Preferences > Desktop & Screen Savers > Screen Saver > Hot Corners, you can set up a corner to put just the display to sleep.