Network connection

[Naughtygirl]

I recently changed the screen on my z3 and now the phone has no network connection I have down graded the software to see if that is the problem I even changed the antenna on the phone as well but I am still having the same problem can you please assist 

[JohnnyDeer]

My WiFi works perfectly but My mobile internet is dead

[Felipe2304]

My cell phone is not network.