Touch Screen horizontal dead zone

Hello I have followed the I fixit instructions as well as others and replaced my faulty sp4 screen with a brand new LG sp5 screen (screen displays perfect) I have also replaced the LBoard (ntrig) with a new one. When I'm in Windows 10 I have a 2 inch horizontal dead zone about 1/4 of an inch down from the top of the screen. Neither finger or pen work in this area,

If I boot in uefi it demonstrates the same behaviour,

Note1: I have also fitted my original ntrig (Lboard) aswell and have the same problem.

Note2: I have run all diagnostic test in surface Diagnostics, done fresh restore on Windows,

Note3: I have not yet replaced the digitalizer cable.

Is it possible I have a defective screen or digitalizer cable?