It is important to check for the following causes if your emails are not being delivered to your secondary email addresses:

1. Check to ensure your email is allowed to be forwarded.
2. Check to make sure email forwarding is configured correctly in your email program.
3. Ensure your email folders are configured correctly.
4. Check that your email is not being blocked due to spam filters.
5. Check that your email provider is not blocking emails from your secondary email address.
6. Check for potential issues with your email server.