How to remove duplicate validation errors - ruby-on-rails

Question

I am having an issue with a sign up form. It was created with SimpleForm, authentication is done with Devise. When submitting the form, if the email or password is blank, it will display the error for this twice. In the user model there are presence validations for the first name, last name, profile name, password, and email. These duplicate errors only appear on the blank email and password fields. Any other blank fields will say so once.
Example:
# Errors Prohibited This User From Being Saved:
Email can't be blank
Email can't be blank
Password can't be blank
Password can't be blank
user.rb:
class User < ActiveRecord::Base
devise :database_authenticatable, :registerable,
:recoverable, :rememberable, :trackable, :validatable
attr_accessible :email, :password, :password_confirmation, :remember_me, :first_name, :last_name, :profile_name
validates :first_name, :last_name, :email, :profile_name, :password, presence: true
validates :profile_name, uniqueness: true,
format: {
with: /^[a-zA-Z0-9_-]+$/
}
has_many :posts
def full_name
first_name + " " + last_name
end
end
registrations/new.html.erb:
<%= simple_form_for(resource, :as => resource_name, :url => registration_path(resource_name)) do |f| %>
<%= devise_error_messages! %>
<div class="formGroupLeft">
<%= f.input :first_name, :input_html => { :class => 'formGroupInput'} %>
</div>
<div class="formGroupRight">
<%= f.input :last_name, :input_html => { :class => 'formGroupInput'} %>
</div>
<div class="formGroupLeft">
<%= f.input :email, :input_html => { :class => 'formGroupInput'} %>
</div>
<div class="formGroupRight">
<%= f.input :profile_name, :input_html => { :class => 'formGroupInput'} %>
</div>
<div class="formGroupLeft">
<%= f.input :password, :input_html => { :class => 'formGroupInput'} %>
</div>
<div class="formGroupRight">
<%= f.input :password_confirmation, :input_html => { :class => 'formGroupInput'} %>
</div>
<div class="formActions">
<%= f.button :submit, "Sign Up" %>
</div>
<% end %>
Why might this be? And how can I attempt to fix it?

Answer 1

Looks like you've specified the devise validatable plugin, which adds email/password validations.
class User
devise :database_authenticatable, ... :validatable
end
Since you're specifying your own validations, I would omit the devise validatable plugin.