Extend Surface issues

Rhino Rhino for Windows
1

Hello, I am pretty new to Rhino, I’ve got a basic understanding for it and I have been learning a few of the different tools.
I am currently using Rhino 5, I have used the Extend Surface tool several times but it wont select a specific surface that I am try to get my hands on.
I created the poly by using the Sweep 1 rail, to make a handle for a kettle but now, when I try to select the surface of the with _ExtendSrf nothing happens.

Does anyone know why?
I’m not selecting the wrong surface but it’s just not working.

Thank you.

2

Depending on how it was created and the input objects, the result of your Sweep might be a polysurface; several surfaces joined together.
You have to extract the surface and maybe untrim it before being able to extend it.