CB doesn't use a password reset link. Users are emailed a temporary password. We'll be redesigning our forgot login to use a password reset link in the future. Joomla uses a password reset link functionality now though so if you're wanting to use that you'll need to turn off CBs functionality for blocking access to com_users by disabling "Redirect URLs" and "Rewrite URLs" in our Joomla system plugin "Community Builder System plugin", but be sure to turn off Joomla registration.