Automatically login a user after they have registered on your website via a Gravity Form

Hi guis,
what can i do if im using for the 1, User Registration Add-On ,soo after SUBMIT we create a user THAN with this plugin nr 2; ‘‘Gravity Forms Auto Login’’ we wil LOGIN USER to our website THAN he leave or logout…

THEN:

after some time he come back to our site and want to use questionar/formular one more time ? Here is a problem, because when he tast EMAIL second time than there is a eror message This email address already registered. Please enter a different email.

How do i solve this problem? PLEASE HELP ME. Our customers cooming to our website many times before they make a ordre…

You can skip registration for logged in users using this:

https://gravitywiz.com/skip-user-registration-for-logged-in-users/