firebase - Is there a way to retrieve an existing notification_key based on a registration id or a notification key name?

Question

Assuming that one has created a device group in Firebase Cloud Messaging, is there a way to retrieve an existing notification_key for a device group after it's been created?

Is there a way to look up the notification_key based on either notification key name or by registration id?

It seems the notification key is only returned on the create method and if the key is ever lost or errors on saving to the the database - it would be impossible to add another registration id to the the key name without a notification_key since it already exists.

Answer 1

Waitting for answers