Hey there,
I am really sorry for the delay of this reply as it is a weekend for us here.
It seems like your facebook user account not accessible when I trying to login.
However, It seems like you hitting this error when you login via Facebook in your site :
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.
Can you double check again with your Facebook app regarding this section whether configure correctly? You can check my attached screenshot below.
After you save your Facebook latest configuration setting, then try login via Facebook from your site and see the issue is it still persists.
By the way, take note of this, it seems like your post is not post in private area, so your site login credentials shouldn't put into your reply section, I already help you move put into your first post site details area, this area only moderator can view it.