Enter the passcode for 2-factor authentication. Even if you have not set up two-factor authentication, this window will open if you use the login function with Email. If not set, log in using SNS.
If you do not complete your e-mail address approval and password and two-factor authentication settings, you will not be able to log in by email. Also, for security reasons, you will be asked to enter it even if 2-step verification is not set.