What is client -2?

I am trying to learn multiplayer scripting. When I print anything from a bp actor on remote window (client window) in my level, it returns as

Client -2: Hello

Update: Its not happening if I put print stirng to begin play. Is it related to chain of events that leads to this one? Bc this event is in a actor in level and its called from an UMG when you click a button.

Update2: It doesnt happen when its called from pawn as well. So my UMG is Client -2 ?

Yeah I don’t know what this is either! Looking for the answer but actually searching for this on google is impossible.