Sorcery with Mongoid isn't persisting the username or email field

gistfile1.rb

class User                                                                                                                                                            
  include Mongoid::Document
  authenticates_with_sorcery!

  attr_accessor :username, :email, :password, :password_confirmation
  attr_accessible :username, :email, :password, :password_confirmation                                                                                                

   field :_id, type: String, default: -> { username.to_s.parameterize } 
   field :username, type: String
   field :email, type: String
   field :crypted_password, type: String
   field :salt, type: String
end

Parameters: {
  "utf8"=>"✓", 
  "authenticity_token"=>"cHo4kDYQ9186rAbcnkje4oi7WXhcw8Sg4/WXwN1EWbs=", 
  "user"=>{
      "username"=>"asdfsdf",
      "email"=>"[email protected]",
      "password"=>"[FILTERED]",
      "password_confirmation"=>"[FILTERED]"
  }, 
  "commit"=>"Save"
}