If this error shows up on your screen, the issue is that there is already an ongoing stream on another mobile device using your account.
Livestreaming is only possible from one device at a time. If you shared your account credentials with someone else or if you're logged in on another mobile device (like a tablet), make sure that the stream is not already running there. Exit the stream there first and then you'll be able to access it on the current device.
Remember, if you would like to share your feed with a friend, you can easily send them an invite code. That way, you can both watch what’s happening on your Bird Buddy at the same time without this issue.