iOS Lock v1 Alias for Azure AD doesn't work and cannot login

Using Lock v1 for iOS, when I typed domain of Windows Azure AD domain in email field on login screen, it does change to enterprise login.

However, I wish to use alias to be able to login instead of Windows Azure AD domain, so if I put [username]@[], it will automatically change to above login. But it’s not working as expected. Is there additional configuration needed?

Also when I try to login, it has “invalid client” error, and I cannot login.

“waad_error”: {
“error”: “invalid_client”,
“error_description”: “AADSTS70002: The request body must contain the following parameter: ‘client_secret or client_assertion’.\r\nTrace ID: 7b2b9c57-3762-41c3-a293-ca0e209f0500\r\nCorrelation ID: 98029e08-b697-4d13-9970-3086d92b4751\r\nTimestamp: 2017-06-02 13:45:21Z”,
“timestamp”: “2017-06-02 13:45:21Z”,
“trace_id”: “7b2b9c57-3762-41c3-a293-ca0e209f0500”,
“correlation_id”: “98029e08-b697-4d13-9970-3086d92b4751”