Enable to create form element

[siwar.bouaoun]

I have created an in place mass then reference polylines and the triangles are model polygons 
When I have clicked create form this error appeared 

[barthbradley]

Did you actually select something to make a form from? 

...shouldn't be that difficult. 

[siwar.bouaoun]

Yes I have selected The line and the triangles 

[barthbradley]

Are you trying to do this? If so, your Triangle is not drawn on the correct workplane.  Tab on the Ref. Point to find a different workplane to draw your triangle on.  

[constantin.stroescu]

Are you sure you have drawn the Profile on the Normal Plan to the curve defined by the Reference Plane?