HEEEEELP ! Particle Mesh facing mode in camera position doesn't work UNREAL NIAGARA

I am trying to set a mesh to point all the time to the camera but I don’t understand why nothing appears in the viewport.

Judging by the mesh preview, is it possible that you’re seeing the disc parallel to the camera direction? or maybe you’re seeing it from behind and so it’s getting culled out? Check in wireframe mode if you can see something. If that’s the case try changing the rotation in those values under the mesh.

If you using quad flat mesh, try to put “Orient Mesh to Vector” to Z -1,0
it gonna be facing properly, good luck!