Update Server from Client does not work AT ALL

Hi guys, Im actually followed 2 tutorial and a post here on the forum to check the mechanism and not I understand it.
So I created a light and a switch and when I request to the server to update the light for all clients HE DOES NOT. Grrr.
This is my blueprint script, easy, short and readable.

I set Send Request To Server to “Run On Server” and Replicate Multicast to “Multicast”.
That logically should work but it doesnt.

269547-immagine.png

269546-immagine.png

I also tried to check Reliable, maybe the Engine is freaking out but no, nothing changed.
And of course I check Reliable on Details along the movement even if It is unnecessary

Only using the server it reply the light on/off to clients.
I followed this tutorial UE4 Replication: Run On Server - YouTube and it works 100% but with Light it doesnt!
Hope somebody can help me and that Moderators publish my request because could be helpful to a lot of guys out there.