I have successfully integrated my two salesforce org using named credentials.
But I want to navigate to a VF Page of a target org from a VF page of source org without asking for credentails.
 

While completing trailhead on Salesforce Customer Identity. I am able to login from google but not from facebook.
Here is the error i am getting.
We can’t log you in because of the following error.
NO_ACCESS: Unable to find a user

I am unable to complete Security Superbadge. My test are passed then also getting this error.Challenge Not yet complete... here's what's wrong: Could not find a user named Samantha Cordero with the Field Sales User profile.Please share screenshots if you have completed.