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When you sign in the app with one user you will get to view all the features of that user/extension and each time you sign in you require authentication(credentials) for that particular user/extension.

This is purely due to security reason and to protect privacy of the users and extensions as you cannot have permission to view or message from another extension/users. In RingCentral each users require their own credentials and authentication for call/message in app or even in API call.

Hello Jason, that would be the expected behavior of our app. You can only view one extension unless you log out and log in to the app with a different extension. Thank you!