No route matches [POST] "/register/sign_up"

This is the first time that I'm receiving this error with Devise. Help
me fix it. Thanks, guys!

api_base_path /api API::Base
home_index_path GET /home/index(.:format) home#index
api_swaggerdashboard_path GET /api/swaggerdashboard(.:format)
api#swaggerdashboard
new_user_session_path GET /login(.:format) devise/sessions#new
user_session_path POST /login(.:format) devise/sessions#create
destroy_user_session_path DELETE /logout(.:format)
devise/sessions#destroy
user_password_path POST /secret(.:format) devise/passwords#create
new_user_password_path GET /secret/new(.:format) devise/passwords#new
edit_user_password_path GET /secret/edit(.:format)
devise/passwords#edit
PATCH /secret(.:format) devise/passwords#update
PUT /secret(.:format) devise/passwords#update
cancel_user_registration_path GET /register/cancel(.:format)
devise/registrations#cancel
user_registration_path POST /register(.:format)
devise/registrations#create
new_user_registration_path GET /register/sign_up(.:format)
devise/registrations#new
edit_user_registration_path GET /register/edit(.:format)
devise/registrations#edit
PATCH /register(.:format) devise/registrations#update
PUT /register(.:format) devise/registrations#update
DELETE /register(.:format) devise/registrations#destroy
new_admin_session_path GET /login(.:format) devise/sessions#new
admin_session_path POST /login(.:format) devise/sessions#create
destroy_admin_session_path DELETE /logout(.:format)
devise/sessions#destroy
admin_password_path POST /secret(.:format) devise/passwords#create
new_admin_password_path GET /secret/new(.:format)
devise/passwords#new
edit_admin_password_path GET /secret/edit(.:format)
devise/passwords#edit
PATCH /secret(.:format) devise/passwords#update
PUT /secret(.:format) devise/passwords#update
cancel_admin_registration_path GET /register/cancel(.:format)
devise/registrations#cancel
admin_registration_path POST /register(.:format)
devise/registrations#create
new_admin_registration_path GET /register/sign_up(.:format)
devise/registrations#new
edit_admin_registration_path GET /register/edit(.:format)
devise/registrations#edit
PATCH /register(.:format) devise/registrations#update
PUT /register(.:format) devise/registrations#update
DELETE /register(.:format) devise/registrations#destroy
root_path GET / home#index

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