Iphone 6s screen turns black after ios 12 update.

My iPhone 6s was working very well on ios 11, until I updated to ios 12.

My screen is black, yet you can see a very faint image when you hold it up to the light. Touch works and I am able to connect it to a minitor and operate the device. The display works sometimes until you try too unjust the brightness. I have tried a new display and battery. This is definitely a software issue. I have tried the things that Apple seggust. Nothing works from the apple suggestions. I have restored the iPhone to ios 13