OLED Replacement Screen went black, will not work.

I purchased a replacement OLED screen from Ifixit. The screen worked for about 6 months. One day the screen went black and the phone is not functional. The phone still makes sounds and vibrations occasionally so I can tell the phone is on. I have tried the reset method: Volume up, Volume down, hold Power button until reset/Apple logo appears... No Luck!

I have taken the phone apart and the connection cords are properly attached.

What do you recommend next?