Nothing special about this type of lobbies. This can be used for a sophisticated server-side skillbased matchmaking that's completely client-driven. There is no way to communicate with others in a lobby. Each one has a unique capability which suits specific use cases: This value should not change, or else it will basically invalidate any matching the players in it did before.
Verify that players have different UserIds.
Matchmaking & Room Properties
Teams Matchmaking You can use this to support teams in matchmaking. Probably the less sophisticated and most used type. Photon Quantum Join the revolution in multiplayer games development: You can rescue your players by checking the "application stats" which tell you how many rooms are available.