add Tool Steel (maraging steel) material, to first list when you choosing material
This material is very popular in industry. One of the most popular from DMLS materials. Automotive/injection molding/die casting/tooling. Fields uses only this material. So buyers who want to get this material after first upload they think that 3D Hub cannot provide it, because it is out of the list. But you can here is Hubs who can provide customers by this material.