Openid Connect from salesforce


I am trying to login from a salesforce community using Auth0 as IdP and salesforce as SP.
Community URL:
I have 2 issues
Ist Issue:
For the app “Salesforce OpenId Connect” I have configured Facebook as social login, when I have entered my fb username and password, it is not working

2nd Issue
For the app “Salesforce OpenId Connect 2” I am always getting the redirect_uri wrong even though I am very certain that my callback URL is entered correctly.
a) Create a web app in Auth0
b) Create a Auth provider in salesforce, got the community callback URL
c) Pasted the callback url in the app, still getting a wrong redirect_uri error why?

I would really appreciate any help !!