Host session isn't working

So I’ve been following this tutorial on youtube on how to set up a multiplayer fps, and I’ve gotten a basic idea on how this works but up to this point in the video 8:08 where he puts the “Get Game instance” to “cast to newgameinstance” then from the option in “cast to newgameinstance” “as new game instance” to “host session” the blue string doesn’t want to go to “host session” when I try connecting the two it doesn’t want to connect. I have two pictures so show what I’m talking about. Can anyone help me figure out why this isn’t working? thank you for taking the time in reading this