If the form is submitted using an email address that already exists in your WP Users, any user details associated with that email address, including the Client Name, Business Name, Address, and Extra Info will NOT be updated, regardless of what the user enters into the form. This is intentional — for security reasons, we do not allow a form submission to alter any existing user data.
The Client Name, Business Name, Address, and Extra Info fields are only populated when creating a new client/user record for the first time.
If you are creating a new form and want to test it, don’t test the form with the same email address you use to login to your WordPress site. Be sure to use a unique email address when testing so that you see all the fields populated. (You can enter a fake email address for testing, it doesn’t have to be a real address.)