Can't use the nested_form_for gem

I am using the nested_form_for gem for the first time. I don't know if this is an issue or if I am using it wrong, but I am getting an "undefined method nested_form_for" error. I have a pretty regular form as you can see:

  <%= nested_form_for @user do |f| %>
        <%= f.fields_for :godfathers do |godfather_form| %>
            <%=  godfather_form.label :name %> <br/>
            <%=  godfather_form.text_field :name %> <br/>
            <%=  godfather_form.label :description %> <br/>
            <%=  godfather_form.text_field :descripti开发者_Python百科on %> <br/>
            <%=  godfather_form.link_to_remove "Remove this godfather" %>
        <% end %>
       <%= f.link_to_add "Add a godfather", :godfathers %>
   <% end %>

By the way, I installed the gem and ran the: rails generate nested_form:install command to generate the nested_form.js file that I included in my layout after the jquery inclusion(<%= javascript_include_tag :default, 'nested_form' %>).

Anyone using this gem as well?

Thanks!

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Everything looks right and if the generator ran the gem should be in place. Have you restarted your server since adding the plugin to your Gemfile?