How to set up an Apple ID with a trusted phone number already in use

To use Apple’s two-factor authentication (2FA) with your Apple ID account–something that the company has effectively mandated for the last few years–you must have at least one “trusted phone number” associated with your account. A trusted phone number can receive a code via SMS or an automated voice call speaking the code to validate a login on a new device. This contrasts with a trusted device, which is any iPhone, iPad, or Mac logged into that Apple ID account.

Read more