s7 edge won't unlock but can use camera... black screen with tasks edge

[Android Central Question]

had the phone charging, sm-g935wb s7 edge.
now it won't unlock. the screen is black all the time but the tasks edge thing works.
if i could tap the home button it will take me to the camera function. which works so the screen is still working.
but i cannot go into the unlock screen. its either black with tasks edge button or the sleep screen with the time and date and 4 notifications.
also i cannot turn off the phone with out doing the power and volume down.
i tried restarting with power and volume down and then the volume up power and home key but when it goes to update screen it shows a crash message of no command. i tried also clearing cache but that failed bcb message showed up.
I'm very confused and have not found a single thing on the internet.

 

[themadscientist]

as for the no command sometimes you have to hold like volume up and power or press each one In cases like this google can be your friend.Recovery no command