Build is in "processing" state from last 7 days ,when adding build to testflight it show error while processing your request ,please try after some time.

You’re now watching this thread. If you’ve opted in to email or web notifications, you’ll be notified when there’s activity. Click again to stop watching or visit your profile to manage watched threads and notifications.

You’ve stopped watching this thread and will no longer receive emails or web notifications when there’s activity. Click again to start watching.