rails undefined method at module

i have a method in my rails module, this is my module

  module Searchable
  extend ActiveSupport::Concern

  included do
    include Elasticsearch::Model
    include Elasticsearch::Model::Callbacks
    index_name Rails.application.class.parent_name.underscore
    puts Rails.application.class.parent_name.underscore
    document_type self.name.downcase

    # you get an error if this shit run first
    module ClassMethods
      def setting_index(arguments)
        settings index: {number_of_shards: 1} do
        ... more code ...

btw. when i'am trying to execute this method(setting_index) at first time i got an error.

but then when i'am trying to execute again this error is gone..

can anyone solve this and give me a clear answer... thanks for your concern :)

require 'active_support/concern'

module Callable
  extend ActiveSupport::Concern
  include Elasticsearch::Model
  include Elasticsearch::Model::Callbacks

  included do
  end

  module ClassMethods
      def setting_index(arguments)
        settings index: {number_of_shards: 1} do
        ... more code ...

  end
end

I think you need to put included module outside included do block.