Enabling User Notifications
The Airship SDK makes a distinction between “user notifications,” which can be seen by the user, and other forms of push that allow you to send data to your app silently.
Enabling or disabling user notifications is a preference often best left up to the user, so by default, user notifications are disabled. However they are easily enabled with a single call to the PushManager instance.
UAirship.Shared().PushManager.UserNotificationsEnabled = true;
UAirship.Push().UserPushNotificationsEnabled = true;
Airship.Instance.UserNotificationsEnabled = true;
Xamarin has a known issue with FCM where disconnecting the debugger will prevent notifications from being received on Android. Rebuilding usually resolves this issue.