Two-step verification can help protect a PlayStation Network account, particularly when it is linked to personal or payment information. But if you lose access to the phone number or authenticator app used to receive verification codes, signing in can become difficult.
Start by looking for PSN backup codes. Sony provides these for account recovery, and an unused code can let you regain access and set up two-step verification again. Check places where you may have saved them, such as email, cloud storage or personal notes. If you are still signed in on a console, you may also be able to change the security method through its security settings.
If neither option is available, contact Sony Support. The recovery process may take time and requires identity verification. Be prepared to provide account details and the serial number of a registered console, along with receipts, order confirmation emails or other information that helps show the account is yours.
After regaining access, enable two-step verification again and store the backup codes somewhere secure. Be alert to scams: Sony will not ask you for your password or verification codes through chat.
Sources: Everyeye.it.