Public and password-protected sites, by default, do not capture your site visitors' names and email addresses (in contrast to email and SAML protected sites).
To collect this data from your visitors for public/password-protected sites, use the Ask Visitors for Name/Email link setting to enable a tracking screen on your site that will ask your site visitors to enter their name and email address before revealing your site's content.
To enable this setting on a new link:
You'll see the option to enable this link setting when you are first creating a link to your site, in the Create Link pop-up window:
To enable this setting on an existing link:
Open the Site's Details view.
Navigate to the Links tab.
Click on the link for which you'd like to enable the setting. (Keep in mind that this setting needs to be enabled for each of your site's links individually.)
Go to the Settings tab of the Link's Details menu.
Note: Only certain user roles can view the Link's Settings tab.
Switch button next to Ask Visitors For Name/Email option.