The problem is, you are doing it simply wrong
The RepNotify is called on the Clients when the Server changes the bool.
So when pressing “F” you want to call a Custom Event that is set to “Run On Server”.
(Note: If you have a Listen Server, so that a client is also a server, use a Switch has Authority to split the server
and client logic).
This event will be called on the server when a client presses F. The Event should change the Bool from true to false or other way
(Note: If you have a Listen Server, you will want to put the logic of this bool change also behind the Switch has Authority exec with
“Authority” and the Client exec gets the custom Event. So both ways, it is called on the server!)
Now, because the server changed the bool, the RepNotify is called and you can decide what to do, based on the bool value.
The things you want to do should NOT be a Multicast. It should just be a normal function that handles the door opening.
Because the RepNotify is somekind of multicast.