Gravity Forms Update User - Change role if product registered

functions.php

// Gravity Forms Update User --> Change role if product registered
add_action( 'gform_user_updated_10', 'change_role', 10, 4 );
function change_role( $user_id, $feed, $entry, $user_pass ) {
    $serialfield = rgar( $entry, '28' ); // Field ID 28 - Serial Number - of My Profile form
    
    if ( ! empty( $serialfield ) ) {
        //update role
        $user_obj = new WP_User( $user_id );
        $user_obj->remove_role( 'subscriber' );
        $user_obj->add_role( 'registered_owner' );
    }
}