My Samsung Galaxy A5 will not turn on at all. How do I fix this?

[AC Question]

I have tried holding down the power button and the down volume button. I have tried holding down the volume up button, the power one and the lock button. I have tried everything I can think off. The phone is definitely not dead, it was at at least 90% charge. And there is not way I can take the battery off. I was using the phone less than an hour ago, and it was fine. What is going on? Does anyone know how to fix this?