Revit Toposurface from dwg contours
I have a survey dwg file with 3D contours that are polylines drawn at correct elevations.
I am attempting to generate a Revit toposurface from the imported contours.
Under "insert" I have tried both import CAD and Link CAD. Followed by going to "Massing and Site", toposurface, create from import. I am sure to only pick the contour layer which has only contours on it.
My toposurface essentially creates a triangle surface with only 3 points and is not reading the contour data.
I have zero experience with Revit so this is likely something I am doing wrong. Is there a certain template file I should be using? Or something else I am missing?
I've attached the photo that shows the green contours compared to the brown toposurface. I also attached the CAD file containing the contours.
I have tried this with multiple different dwg files containing contours and get similar results. Please help me as I have wasted 1.5 work days on what should have been a 10 minute job.
Thanks in advance!