UE4 Blueprint Multiplayer Tutorial issue/question

Hi Guys
I am following the UE4 blueprint multiplayer tutorial and everything was running well till I tested at the end of slide 16 - player card setup.
Instead of my host server starting a game that the client can join, it starts a game and the client is automatically joined without having to search for the game (as per the tutorial)

This is the tutorial:


Any ideas on what could be going wrong?