trying to login with user or email

I'm trying to mess with the login so that you can login using both an email address and a username, but can't get it to work. I've been mostly trying to follow the instructions in this how-to article on the Devise Wiki (https://github.com/plataformatec/devise/wiki/How-To:-Allow-users-to-sign-in-using-their-username-or-email-address). Rails doesn't throw any errors, but when I try to log in, it won't recognize the login for my user. If I retrace my steps back to where I was this morning (which I've done 3-4 times now), it will let me log in using an email/password.

Can you please take a look and let me know what you think?