Possess pawn not working on listen server

Hi, I’m trying to spawn a new character then make it possess by a Controller when he join the server.
It works on the server side but not on the client side. The controller (client) is “attached” to the pawn but he can’t control him and I don’t understand why … But it works when I launch 2 instances of the game not in standalone mode but directly in the editor.

This function is call when I new controller come (with the function PostLogin in c++)