Hi all, 

I have an assembly with two parts. P1 is an imported stl from a scanned body. I am drawing at 3D sketch with points along the contours in P1. I then draw a sketch in P2 and uses the points from the sketch in P1 for relations, e.g. coincident, and then extrude the sketch to build the body.
This have worked fine for quite some time, but for some reason I can no longer "high light" the P1 sketch from P2 to relate. 
Can someone help me figure out what I'm doing wrong?

This is my first time using a scanned part, so please bear with me if i ask obvious questions.

Running Solidworks 2025 Pro SP3.0

Thanks!

Edit:

Clarification:

The sketch from P1 IS visible from P2 (grey) and when I click the P1 sketch it high lights, but I can't mark the points from P2. That is I can't ctrl-click P1 point and P2 line to make the relation. 
Hope that makes more sence.