Set Niagara Variable (color / vector) in blueprint

Hello, everyone.
I’ve already searched on internet about this for few days and still can’t find the answer to my situation.

I want to change the color of a sprite in a niagara system when a certain event is triggered. What I do, is call this node to change the color.

However, this doesn’t do anything at all. If I run this same node in ConstructionScript it works as expected, but if I call an event in runtime, this won’t work at all.

Any suggestions?