Steam invite automatically fails

I’m attempting to set up a Steam Lobby, but when I attempt to send an invite to my friend, it just automatically fails. The invite never shows up on his computer at all.

I don’t know if something’s wrong with my code, or if I need to register the game with Steam or something along those lines. The Game Instance is currently inheriting from Advanced Friends Game Instance. Does anybody know?

Turns out the solution is to create an advanced session first