If I am not logged into facebook on browser, then I was getting following error:
You are not logged in: You are not logged in. Please log in and try again.
If I am logged into facebook then I was getting below error:
URL Blocked: This redirect failed because the redirect URI is not whitelisted in the app’s Client OAuth Settings. Make sure Client and Web OAuth Login are on and add all your app domains as Valid OAuth Redirect URIs.
I was using WP Social Login plugin on Wordpress installation.
Below is the solution.
