code: def send_sms_confirmation!
        return false if _TC_sms_blocked
        return true  if sms_confirmed?
        return false if _TC_phone_number.blank?
  
        format_phone_number
        confirmation_code = TwilioContactable.confirmation_code(self, :sms)
  
        # Use this class' confirmation_message method if it
        # exists, otherwise use the generic message
        message = (self.class.respond_to?(:confirmation_message) ?
                     self.class :
                     TwilioContactable).confirmation_message(confirmation_code)
  
        if message.to_s.size > 160
          raise ArgumentError, "SMS Confirmation Message is too long. Limit it to 160 characters of unescaped text."
        end
  
        response = TwilioContactable::Gateway.deliver_sms(message, _TC_formatted_phone_number)
  
        if response.success?
          update_twilio_contactable_sms_confirmation confirmation_code
        end
  
        response
      end
docs: Sends an SMS validation request through the gateway