Hello @Anonymous - let me introduce you to the Invisible Line Trick....
Open your family. Go to an elevation view. Draw a vertical invisible line from the geometry - make it long enough to go through the cut plane of your plan view. Reload the family. You will see the Symbolic line. I use this trick a lot when I model bulkhead families and wall hung TVs (yeah, that's quite a contrast).
Here's the rationale - when the invisible line touches the cut plane, it tells the cut plane to look at it. Kind of like tapping someone on the shoulder and saying "Hey, I'm here!"
Rina Sahay
Autodesk Expert Elite
Revit Architecture Certified Professional
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