Two-factor authentication (2FA) is a secure way for companies like Apple to protect accounts. When attempting to log into an iCloud account, such as connecting your child's iMessage account to BrightCanary, Apple will send a code to your child's iPhone, iPad, or Apple Watch. You need to enter this code into the BrightCanary app to continue the login process. In addition to your child's iCloud password, this code verifies to Apple that the login attempt is coming from you or your child.