Whats the meaning of "client -2"?

Hello, Im calling a function that is on my ThirdPerson BluePrint from a widget.

Im working on a multiplayer game (Replication). So when i click on my button widget it will fire a Function from my ThirdPerson BluePrint and print something but, ingame, when i press that button, the entity of that printString is “client -2” even if Im pressing the button on client 1 or 3 or 4 etc etc. So im here to try to understand what is that “client -2”
Thank you.

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