Alienware laptop not waking from sleep mode, instead is restarting

I purchased an alienware laptop about 5 months ago, and everything was working fine until about a week ago when i noticed whenever i pressed the power button to wake up my laptop, it would go through the boot process and end up in the start screen. Now whenever i try to wake up my computer, it is acting as if it was turned off. I turned off hibernation mode to see if that was the problem, but it is still happening. Any ideas on what the problem could be or how i could fix it would be greatly appreciated!