Routing Error No route matches [POST] "/users/sign

routes.rb

Rails.application.routes.draw do
  devise_for :users
  # get 'prototypes/index'
  # get  'devise/registrations'#new
  root to: "prototypes#index"
  resources :prototypes do
    resources :comments, only: [:create, :edit] do
    end
  end
  resources :users, only: :show
end

application.html.erb

<!DOCTYPE html>
<html>
  <head>
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>ProtoSpace</title>
    <%= csrf_meta_tags %>
    <%= csp_meta_tag %>
    <%= stylesheet_link_tag 'application', media: 'all', 'data-turbolinks-track': 'reload' %>
    <%= javascript_pack_tag 'application', 'data-turbolinks-track': 'reload' %>
    <link href="https://fonts.googleapis.com/css?family=Noto+Sans+JP:400,700,900&display=swap" rel="stylesheet">
  </head>

  <body>
    <header class="header">
      <div class="inner">
        
        <div class="nav">
          <div class="nav__left">
            <%= link_to image_tag("logo.png", class: :logo), root_path %>
          </div>
      
           <% if user_signed_in? %>
             <div class="nav__right">  
                <%= link_to "ログアウト", destroy_user_session_path, method: :delete, class: :nav__logout %> 
                <%= link_to "New Proto", new_prototype_path, class: :nav__btn %> 
             </div>  
           <% else %>
              <div class="nav__right">
                <%= link_to "ログイン", new_user_session_path, class: :nav__btn %>
                <%= link_to "新規登録",  new_user_registration_path, class: :nav__btn %>
              </div>
            <% end %>
        </div>
      </div>
    </header>
    <%= yield %>
    <footer class="footer">
      <p class="copyright">Copyright © PROTO SPACE All rights reserved.</p>
    </footer>
  </body>
</html>

実装しているさい一つは登録できたのですができなくなってしまいました。
ルーティングも定義されているのに間違えがわかりません。
宜しくお願いします。