Please help me with the solution for the offset curve

I used a ‘clipper’ to make an offset curve inside the panel.
The plane setting was resolved using the ‘Deconstruct Rectangle’.
However, when I zoomed in and looked closely, I found an excitation on the panel plane.
To solve this problem, I used ‘offset on surface’ to solve it, but this time I’m not able to delete the intersection line inside.

Question1) How do I fix the plane setting when I use the ‘clipper’?
Question2)How can I trim an internal intersection if I use ‘offset on surface’?

panel_question1.3dm (34.4 KB)
panel (11.7 KB)

Clipper only wants planar curves.
Offset on Surface is good, but you forgot to join the curves after Brep Wireframe.

It’s simply worked out.
Thank you.