Note that you may not be able to see the authentication code if the mobile phone, email address, or the two-factor authentication app registered to the setting of two-factor authentication is no longer valid, and therefore may not be able to log in.
In such case, you can use the “recovery code” for authentication.
Please save the recovery codes (10 codes), which will be provided when you set up two-factor authentication.
＜Related questions＞
Q. How do I set the two-factor authentication?
Q. What is a recovery code?