it is very funny, but https://www.paypal.com/webapps/auth/protocol/openidconnect/v1/userinfo is not correct, too.  this url is correct https://api.paypal.com/v1/identity/openidconnect/userinfo/. you can see it on https://developer.paypal.com/webapps/developer/docs/integration/direct/log-in-with-paypal/js_button/#registerSite - 4. Get User's PayPal Profile Data