Why my screen won't display anything?

Hi, my Huawei P9 lite has a cracked screen and recently gave me flickering problems which stopped when i removed the lock screen pattern.Right now i can’t see anything on my screen it went off when the battery was completely out of power , when i press and hold the power button it lights up for a few seconds then nothing happens.The alarm still goes off add it’s still able to charge but nothing will display on the screen, i tried to press and hold the power and volume button still nothing appears on the screen it just lights up then goes off.

What could be the problem?

Thank you.