Face ID error after screen replacement with component swap

Hello,

I replaced the screen on my iPhone XR with an OEM screen from a donor device. I actually took the whole donor device except the logic board, and I swapped all the front camera assembly and ear piece components from the old screen to the new, so theoretically FaceID should be functioning, but it is not and I wonder if you fine folks could help me diagnose the issue.

It gives me the “move a little higher/lower” error. The odd thing is, the front camera works perfect, and portrait mode on the front camera works perfect as well. I thought this meant the dot matrix projector most be functioning, so I’m not sure what to look at when I take it apart. Flood Illuminator or IR camera?

Any points from those more experienced would be appreciated!