There are many possible reasons why you might not be receiving your 2FA email. In most cases, it might be an issue with WordPress having trouble sending emails or a node in the chain is, for one reason or another, not forwarding the email properly. WP 2FA comes with a built-in email tester that can allow you to verify that the email is being sent. However, this is not the entire story, and as such, it is worth taking a minute to understand how emails are sent and delivered. In a nutshell, WP 2FA composes the email and forwards it to WordPress, which then sends the email to the configured SMTP server. WordPress does this by using a function called wp_mail, which is built on the PHP’s mail function. While this tends to work pretty well out of the box, it can be prone to issues.