StartGame (https://titleId.playfabapi.com/Matchmaker/StartGame) currently requires a GameMode but I'm confused over where this comes from.
When adding a new build in PlayFab (multiplayer/server/builds/new) there is nowhere that I can see to specify supported GameModes. I do see a tab in Legacy but it says "cannot create game modes: no builds". The legacy built tab says: "No builds found". But the Servers tab definitely has the build added in the list.
I will start looking into using the admin REST api https://titleId.playfabapi.com/Admin/ModifyMatchmakerGameModes but I feel I'm on the wrong path here.
Thanks