rake_routes.rb

 create_index GET        /messages/support/warranty(.:format)                           messages#index                                                                                │·
              GET        /messages/support/register(.:format)                           messages#index                                                                                │·
              GET        /messages/support/exchange(.:format)                           messages#index                                                                                │·
              GET        /messages/support/contact-us(.:format)                         messages#index                                                                                │·
              POST       /messages(.:format)                                            messages#create

routes.rb

    resources :messages, only: [:create], as: 'create' do
      collection do
        get 'index', path: '/support/warranty'
        get 'index', path: '/support/register'
        get 'index', path: '/support/exchange'
        get 'index', path: '/support/contact-us'
      end
    end