Help with Lofted Bend

Attached is an assembly of a Square to Round. I am sure what I am about to ask I have done before but I can't seem to get it to work now. Anyway here it is.

I need to add a 50mm Edge Flange on the top side of the transition, but no matter what I do I cannot seem to do it. Does anyone know a work around

Cheers

Damian

SolidworksSheet Metal