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Hi,I have a weird situation about trying to get device token from iPhone devices. I applied the rules about registration to remote notifications. In didFinishLaunchingWithOptions, UIApplication.shared.registerForRemoteNotifications() is implemented. Also isRegisteredForRemoteNotifications is true. However, didRegisterForRemoteNotificationsWithDeviceToken is not getting called. The most weird thing is while didRegisterForRemoteNotificationsWithDeviceToken is called in iPhone XR, but didRegisterForRemoteNotificationsWithDeviceToken is NOT CALLED in iPhone X, iPhone 8 sometimes. I also didFailToRegisterForRemoteNotificationsWithError is not called. Because there is no failed situation. All permission is given etc ...I can't find any specific answer to my problem. didRegisterForRemoteNotificationsWithDeviceToken is not working some devices sometimes.Thanks.