Issues in Notification Hub

Hi @Arpit ,
Welcome to the Microsoft Q&A Platform!
The error message indicates that the Notification Hub is unable to find any target applications for the notification you are trying to send.

• Confirm the Private Key, Client Email, and Project ID in the Notification Hub settings match the Firebase project credentials.
• Download the private key JSON file from Firebase Console under Service Accounts.
• Open the Azure portal and navigate to Notification Hub > Settings > Google (GCM/FCM).
• Ensure FCM settings are configured for v1 API and include the private key JSON.
• Verify that devices are registered with a valid registration ID or installation ID.
• Use the Test Send option in the Notification Hub to confirm active registrations.

Ensure the payload is in the correct FCM JSON format.

{
  "message": {
    "token": "device_token_here",
    "notification": {
      "title": "Test Notification",
      "body": "This is a test message"
    }
  }
}

• Use the Tracking ID (5da2a253-53eb-4416-9655-80da98ea8a0b) to check detailed logs in Azure Monitor or Application Insights.
• Test FCM credentials directly via Postman to ensure they work.
• Re-register devices if previously registered with older GCM configurations. Ensure compatibility with FCM v1. https://learn.microsoft.com/en-us/azure/notification-hubs/
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