Integration of Cloud connected devices (security camera ) with Smart-thing cloud

I am trying to integrate Cloud connected devices (security camera) with Smart-thing cloud. For that i have created a project in developer workspace with cloud connector of Smart thing schema. This is based on the device handler . There is no custom device profile. After deployment for the test , I am not able to test it .
When i am trying to add it in a smart-thing mobile app on iOS phone (Add device-> My Testing device) then it shows loader screen and disappears. there is no error, No login screen (authorization screen)
I am using LWA (Login with amazon) as Oauth2.0 server ( Created LWA profile and added smart-thing oauth callback in allowed return url).

I have tried other Oauth2.0 servers also but same problem.

These Oauth2.0 servers are working for Alexa

Does it require any whitelisting of developer account to work ?