How to allow email blank in user table which is created using devise and cancan

I have a user model in which username and* email* field, i am login
with username when i am creating user i want it’s email may be blank,
but
when i am register user from another model it gives error User email
can’t
be blank
.
I already make changes email field in confgi/devise.rb, but it doesn’t
work.

Here is My User model

class User < ActiveRecord::Base

has_and_belongs_to_many :roles

devise :database_authenticatable, :registerable, :rememberable,
:token_authenticatable, :trackable,
:validatable, :timeoutable ,:lockable, :recoverable ,
:authentication_keys => [:username]

attr_accessible :email, :username, :password, :password_confirmation,
:remember_me, :role_ids, :roles
validates :email , :presence => false
end
Please, let me know where i am wrong.

Thanks,
Tushar P…

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