An error indicating that the current user is not authenticated, and no user record was available.
- iOS 8.0+
- macOS 10.10+
- UIKit for Mac 13.0+Beta
- tvOS 9.0+
- watchOS 3.0+
- Xcode 8.0+
This error can occur if the user is not logged in to iCloud.
An iCloud account is required to read or write from the private and shared databases, or to write in the public database. Prompt the user to go to Settings and sign in to iCloud.