title: Rails Devise Requires Email
body: <p>I have seen many threads on them, however none solved the issue for me (other people's issues were solved). I am trying to sign in via username password and no email, but I get<br>
  SELECT  "users".* FROM "users"  WHERE "users"."email" IS NULL LIMIT 1</p>
  
  <p>Here is my code:</p>
  
  <pre><code>class User &lt; ActiveRecord::Base
   #devise :omniauthable
   include DeviseTokenAuth::Concerns::User
   devise :authentication_keys =&gt; [:username]
  end
  </code></pre>
  
  <p>In devise.rb:</p>
  
  <pre><code>config.confirmation_keys = [ :username ]
  config.authentication_keys = [ :username ]
  config.case_insensitive_keys = [ :username ]
  config.strip_whitespace_keys = [ :username ]
  </code></pre>
  
  <p>I have really no idea where the error could be..</p>