Rails 4 fields_for not displaying field -

i have 2 models create 1 form. tried following railscasts tutorial, can't nested fields display on form. how can make these nested fields appear?

models

class poll < activerecord::base   has_many :poll_answers, :dependent => :destroy    accepts_nested_attributes_for :poll_answers, allow_destroy: true end  class pollanswer < activerecord::base   belongs_to :poll end 

controller

class pollscontroller < applicationcontroller    def new     @poll = poll.new     2.times { @poll.poll_answers.build }   end    private    def poll_params     params.require(:poll).permit([       :question,       poll_answers_attributes: [:answer]                 ])   end end 

view

<%= form_for(@poll) |f| %>    <div class="field">     <%= f.label :question %><br>     <%= f.text_field :question %>   </div>    <% f.fields_for :poll_answers |pa| %>     <p>hello       <%= pa.text_field :answer %>     </p>   <% end %>    <%= debug @poll.poll_answers %>    <div class="actions">     <%= f.submit %>   </div> <% end %> 

you missed =

 <%= f.fields_for :poll_answers |pa| %>     <p>hello       <%= pa.text_field :answer %>     </p>   <% end %>