A. SMS authentication using a phone number is optional, so you can still use the content even if you skip the authentication. However, the following may be the cause.

(There is no difference in service whether or not you are certified.)

・The phone number is incorrect

- The smartphone is not capable of receiving SMS
・The settings are not set to receive SMS.
・You are refusing to receive SMS from anonymous numbers or overseas.

If none of the above applies and SMS authentication is not successful, please check the following.

・The surrounding network may be congested, so please try again later.
・Please reload the SMS authentication screen.
・Please reinsert the SIM card.
・Please make sure you are able to receive calls from blocked numbers or overseas numbers.
- For details on how to set up your reception, please contact the mobile phone company that provided you with your SMS.

If the above does not resolve the issue, please try reinstalling the app or authenticating via voice guidance (authentication by phone).
* However, to prevent fraudulent use, reinstallation of the app is limited to twice a month.
Please note that if you exceed the limit, you will not be able to log in yourself.