这让我发疯了一段时间.您必须在开发者控制台中启用实时多人游戏支持.它是游戏服务"选项卡上链接的应用程序"中的选项之一.另请参见此故障排除页面，该页面链接到

This was driving me crazy for a while. You have to enable real-time multiplayer support in the Developer Console. It's one of the options in Linked Apps on the Game Services tab. See also this troubleshooting page which links to these instructions