Update README.md, use more specific url for setup email on error 422

README.md

@@ -33,7 +33,7 @@ You can also join *git* slack channel on [SoM IRT Slack channel #med-svc-gitlab]
 
 ## <a name="422-error" ></a> Why do I get "422 Error" when sign-in?
 
-If you get this error the first time your sign-in, most likely, your email contact information in [StanfordYou](https://stanfordyou.stanford.edu/)
+If you get this error the first time your sign-in, most likely, your email contact information in [StanfordYou](https://stanfordyou.stanford.edu/main/SYApp?action=change_email)
 is either private or doesn't exist. It can be caused by sponsorship changes. The email must be in format of \<your sunetid\>.stanford.edu.
 
 gitlab.med.stanford.edu service requires your email address to log you in, and the email must be in stanford.edu domain and fully sponsored.