This error can show up for several reasons:
1. A user does not exist in the system.
2. User retrieval is forbidden in the Dashboard application settings. (Setup it here).
3. If you try to update a user but you are not this user or account owner.
4. If you try to update or delete a dialog but you are not an owner of the dialog or account owner.
5. If you created an application session instead of a user session.
6. If a user tries to retrieve chat messages for a chat dialog while they are not in the occupant’s list.
For more information on this see:
Server API - Authentication
Documentation related to specific QuickBlox SDKs:
iOS SDK - Authentication | iOS SDK | QuickBlox
Android SDK - Authentication | Android SDK | QuickBlox
React Native SDK - Authentication | React Native SDK | QuickBlox
Flutter SDK - Authentication | Flutter SDK | QuickBlox
Feel free to check our official documentation for more information that will help you to integrate QuickBlox services into your applications / projects or contact our Support team by submitting a ticket if you have any other questions.