Sign in with Apple: How do I know which email address I registered with Nikkei Asia?
If you chose to share your email address, then it could be your Apple Account email address. If you chose to hide your Apple Account email address, you need to check the private relay email address you used for Nikkei Asia.
To view which email address is connected to Sign in with Apple, please follow these steps.
On your iPhone or iPad
Open the Settings app on your phone.
Tap your "Apple Account settings".
Select "Sign in with Apple".
Find "Nikkei Asia" from the list and tap it. You should see either your Apple Account email address or an email address that ends with @privaterelay.appleid.com.
On the web
Sign in at https://account.apple.com
Click "Sign-In & Security" on the left side menu.
Click "Sign in with Apple".
Find "Nikkei Asia" from the list and click it. If you see an email address that ends with @privaterelay.appleid.com, then that is the email address you registered with Nikkei Asia. If you don’t see anything, you are registered with your Apple Account email address.