In my registration page i have 2 field, with email and password, now i trying to add new field with name, so to file /app/views/devise/registrations/new.html.erb and /app/views/devise/registrations/edit.html.erbi added 
<div class="form-group">
<%= f.label :name, "Name" %>
<%= f.text_field :name, class: "form-control", :autofocus => true %>
</div>
and after this edit my website show this error:
 Rendering devise/registrations/new.html.erb within layouts/application
My new.html.erb :
<div class="panel panel-default">
  <div class="panel-heading"><h2>Registration</h2></div>
    <div class="panel-body">
<%= form_for(resource, as: resource_name, url: registration_path(resource_name)) do |f| %>
  <%= devise_error_messages! %>
          <div class="form-group">
            <%= f.label :name, "Name" %>
            <%= f.text_field :name, class: 'form-control', :autofocus => true %>
          </div>
          <div class="form-group">
    <%= f.label :email %><br />
    <%= f.email_field :email, autofocus: true, class: 'form-control' %>
  </div>
  <div class="form-group">
    <%= f.label :password %>
    <% if @minimum_password_length %>
    <em>(<%= @minimum_password_length %> characters minimum)</em>
    <% end %><br />
    <%= f.password_field :password, autocomplete: "off", class: 'form-control' %>
  </div>
  <div class="actions">
    <%= f.submit "Sign up", class: 'btn btn-primary' %>
  </div>
<% end %>
    </div>
      <div class="panel-footer"><%= render "devise/shared/links" %></div>
    </div>
Did I make a mistake somewhere?
__Edit
after restart heroku i get new error:
Completed 500 Internal Server Error in 2ms (ActiveRecord: 0.0ms)
app/controllers/application_controller.rb:11:in `configure_permitted_parameters'
my: /app/controllers/application_controller.rb
class ApplicationController < ActionController::Base
  protect_from_forgery with: :exception
  before_filter :configure_permitted_parameters, if: :devise_controller?
  protected
  def configure_permitted_parameters
    devise_parameter_sanitizer.for(:sign_up) << :name
    devise_parameter_sanitizer.for(:account_update) << :name
  end
end
 
     
     
    