Fill mode option was disabled in the newly created geometry

[qoimzslm]

Hi, I would like to create my own solid geometry, for example, a solid triangle. I am trying to create in some ways.

1. Through the sketcher menu, I make a 2D triangle shape and then extrude it to 3D.
2. Through the part menu, I create a solid cube and do a chamfer to make it triangular shape rather than a cube.
   However, when I try to add the solid object by the above way to DSPH simulation, all of them are formed as "Face" in the Fill mode feature, and I'm unable to change it a solid object. How can I create a solid/full object with my design shape in DesignSPHysics?

This question has similar issue with case #201 which has not yet close
Thank you very much for your reply.