within updated M9 Release, AuthHub endpoint - “factor/v1/PasswordAuthenticator” is not sending complete response for mobile channel.
The “userName” param has not being sent in updated response, which is causing parsing issue at mobile client.
"userName": "123456789", //this field is not available for mobile flows
Release : M9
Fix was released in M9 / Oct 5 Release .
You need to make sure AuthHub is updated to M9/ OCT 05 and onward release to see the username parameter in the response