Logitech Type+ flashing blue; iPad Air 2 won't wake

When I leave my iPad Air 2 for some 5 minutes and return, my asleep iPad refuses to wake when I press the power button. I press the power button on my keyboard case (Logitech Type+) and the little light on it flashes blue. As of writing this has happened 3 times today and right now it just isn't waking. Any ideas?