Hi there,

Just to confirm, are you requesting the Personal Information question group for both the Primary and Additional registrants on your events?

So in the event editor, both of the ‘Personal Information’ checkboxes show HERE are checked?

If so you can use a function like this:

https://github.com/eventespresso/ee-code-snippet-library/blob/master/checkout/tw_ee_force_unique_emails_for_registrations.php

You can add that to a custom functions plugin on your site, we have some documentation on creating one here:

https://eventespresso.com/wiki/create-site-specific-plugin-wordpress-site/