The CPU and RAM is okay for creating session but key part is GPU. Your GPU needs to have 4 GB of VRAM. If it has 2 GB, it will not work.

For the full explanation of the error: Error Domain=GKErrorDomain Code=35 "The requested operation could not be completed because you are not signed in to iCloud." UserInfo={NSLocalizedDescription=The requested operation could not be completed because you are not signed in to iCloud., NSUnderlyingError=0x600000c8df20 {Error Domain=GameDaemonCore.PseudonymManagerError Code=0 "(null)"}} Kindly note that my localPlayer is authorized but I cannot get into matchmaking due to iCloud error. I even added iCloud Container within entitlements but didn't work.

Hi, I've been dealing with the same problem. As far as I figured out, we need to create WindowGroup with .plain parameter but it is in SwiftUI RealityKit, not Unity3D. Have you found any solution to this problem? @UnrealMitch EDIT: A possible solution is setting window style Info.plist in Xcode. Under "Application Scene Manifest", change "Preferred Default Scene Session Role" to "Window Application Session Role". At least, it is opening up Game Center Matchmaking View Controller in my project. Regards, Melih