Trouble using GetComponentsInChildren to change color on projectile hit

Surrealism 12 months ago updated 12 months ago 1

Hi, I'm trying to get all Material from the child of current object to emit white color as HDR on trigger enter from player projectile, currently it is giving me an error saying "Object reference not set to an instance of an object", anyway to solve it? And is this the best graph to use to achieve the desired result? 

Bolt Version:
Unity Version:
Scripting Backend:
.NET Version (API Compatibility Level):

Any one knows this issue? I have transited to shader graphs now, so will shader graph be easier to control the emission?