Touch Screen Completely Unresponsive

All of a sudden, my iPad Pro 10.5” touch screen is completely unresponsive. The home button and side and top buttons work. I am able to do a hard reset. However, each time it comes to the screen where I am required to enter the passcode, the touch screen will not accept input. If I try to do a regular power down, I see the power-off slide, but cannot use it as the screen does not recognize my touch. I have removed the screen using iFixit’s excellent tutorial and have reseated the 4 screen connectors. Still no go. The display itself works fine with all pixels displaying. Does anyone have a suggestion? Thanks!