add_action('wpf_tags_modified', 'my_wpf_delete_user', 10, 2);

function my_wpf_delete_user( $user_id, $user_tags ) {

    if( ! wp_fusion()->user->has_tag('GFTB Full Membership - Activated', $user_id) && ! user_can($user_id, 'manage_options') ) {
        wp_delete_user( $user_id );
    }

}


add_action('wpf_got_contact_id', 'my_wpf_delete_user_by_cid', 10, 2);

function my_wpf_delete_user_by_cid( $user_id, $contact_id ) {

    if( $contact_id == false && ! user_can($user_id, 'manage_options') ) {
        wp_delete_user( $user_id );
    }

}