A display where the touch screen is only partially working almost always indicates a damaged digitizer, requiring replacement of the screen; the damage may or may not be visible. Just went through pretty much the exact same issue with my grandson's iPhone X after a drop and ended up replacing the screen to fix the problem.
📢Your iPhone X stuck on black screen but can still work and vibrate? Moreover, you can still hear sounds and get text messages. No worry about this issue asLet’s tell you how to fix top of iPhone screen not working in no time. Way 1: Restart or Force Restart iPhone. Way 2: Adjust 3D Touch Sensitivity. Way 3: Free Up Storage. Way 4: Remove Your iPhone Case. Way 5: Clean iPhone Screen or Fingers. Way 6: Update to Latest iOS System.NrA3oM.