flat pattern of a loft cone

Hello, I'm trying to unfold these parts to get a flat pattern. I'm using insert bend feature but with no success. Any other way of doing it?

Ok so I try doing it with a lofted ben in sheet metal. It worked at first, I was able to flatten the cone part but know it doesn't want to flatten anymore. It's telling me that I must select a fixed planar or a linear edge. I don't know what I'm doing wrong.

Here is a pack and go of the parts.