Display has stopped turning off after set time of 5 minutes

Until recently the display would turn off after the 5 minutes that is set in power options/choose when to turn off display, but now for the last few days it isn't turning off after 5 minutes or any number of minutes, it just stays on.

What could be causing this problem?

Signed,
shewood1

This is often caused by something still running, holding the system alive so you need to verify that is not the case here. Also, have you rebooted - that alone often fixes sleep problems.

Another thing I have had to do is change the setting to say 10 minutes, hit Apply, then change them back.