Why is there a reversed picture, grey shadow acroos the screen?

I am testing a new LCD on an iPhone 7 plus. The two new screens both have an inverted/reversed picture. The LCD flickers, and has a grey shadow across the center of the screen. The original LCD had no picture but did have backlight and hepatic feedback from the digitizer working. I find it hard to say I got two crappy parts from the same place. Any suggestions? Does any of the other original parts need to be installed on new LCD to test it?