We're assuming that you are able to receive emails from other third-party applications or external sources.
This has been observed that when you have NoScript add-on for Mozilla Firefox enabled, or similar extension enabled for Google Chrome. PolicyPak email service will unable to send the email-based two-factor authentication code via email.
To be sure, this highlighted function on PP website doesn't work when NoScript is enabled for either Mozilla Firefox or Google Chrome.
This is a screenshot of NoScript plug-in Mozilla Firefox as on October-2019. It may look different now.
Add URL policypak.com website in the trusted site section of NoScript plug-in.