Material issue when exporting to unreal engine

Hi everyone.
I have an issue on the material when I export some clothe I use it on my character on CC4:
_I use some fbx file (as accesory) that I put on my character and then I use transfer skin weight to be able to manipulate it.
The issue I have is that when I export back in Unreal engine and I put the material back on it I don’t have the material properly working: I have just a plain color on my clothe and not the material property.
I have made this manipulation many time and it use to work perfectly so I don’t understand why it stop to work.
I don’t know it it is an unreal engine issue or a CC4 .

Thank you very much