No route matches [POST] "users/sign_up" - ruby-on-rails

Question

new to Rails here. I am wondering if anyone can help me with the problem that I am having. So basically, I am trying to use devise to add user authentication to my app. But every time I tried to submit the signup form, a warning "No route matches [POST] "users/sign_up"" appears on the app.
Here are my routes.rb
Rails.application.routes.draw do
get 'home/index'
root 'home#index'
#devise_for :users, controllers: { sessions: 'user/sessions' }
devise_for :users, path: 'auth', path_names:
{ sign_in: 'login', sign_out: 'logout', password: 'secret', confirmation: 'verification',
unlock: 'unblock', registration: 'register', sign_up: 'cmon_let_me_in' }
devise_scope :user do
get 'sign_in', to: 'devise/sessions#new'
end
resources :workspaces do
resources :items
end
end
Also, my new.html.erb on the devise/registration looks like:
<h2>Sign up</h2>
<%= form_for(resource, as: resource_name, url: new_user_registration_path) do |f| %>
<%= render "devise/shared/error_messages", resource: resource %>
<div class="field">
<%= f.label :email %><br />
<%= f.email_field :email, autofocus: true, autocomplete: "email" %>
</div>
<div class="field">
<%= f.label :password %>
<% if #minimum_password_length %>
<em>(<%= #minimum_password_length %> characters minimum)</em>
<% end %><br />
<%= f.password_field :password, autocomplete: "new-password" %>
</div>
<div class="field">
<%= f.label :password_confirmation %><br />
<%= f.password_field :password_confirmation, autocomplete: "new-password" %>
</div>
<div class="actions">
<%= f.submit "Sign up" %>
</div>
<% end %>
<%= render "users/shared/links" %>
Thank you for your help.