Opening lid no longer wakes laptop

I have a Samsung laptop running windows 8. Up until today, closing the lid would put it to sleep and opening the lid would wake it. This morning when I opened the lid it wouldn't wake up until I pressed the power button. I've tried changing all settings under the power options but nothing works. Something I've noticed is that with the four lights on the front of my laptop, previously the three blue lights would turn off while sleeping and the green charging light would stay on. Now two of the blue lights turn off while the third slowly pulses. This problem came up out of nowhere as I haven't downloaded anything or changed any options. Any ideas?

try

Thanks, but I've already tried changing those settings and nothing has worked.

google reset cmos

Or, and it's much simpler, just do what I do and completely disable SLEEP and HIBERNATE, two things that MS has never gotten right since Windows was invented. One or the other has often reared its ugly head to really screw up someones PC.
Personally, I feel like "minus crud is cool!" (quote: Mike Warnke)

The fewer things that are going on in my computer, that can screw things up, the better I feel about it, and the better it works.
So, all 20 of my computers, have just two states, those being ON and OFF. Anything else is problematical.

I incorporate a Boot UP tweak, that greatly speeds up the Boot up of any Windows PC, by at least 27 sec's.
I also use a Quick Shutdown shortcut, that shuts down most of my PC's in just five to eight seconds.

Try it..... you might just like it.

TechnoMage