Profile: NathanG920

add_filter('option_wpcf-fields', 'fill_my_users');
function fill_my_users($fields) {
    foreach ($fields as &$field) {
        if ($field['id'] == 'your-field-slug') {
            $field["data"]["options"] = array();
            $users = get_users();
            foreach ($users as $user) {
                $key = $field["id"] . $user->user_login;
                $field["data"]["options"][$key] = array(
                    "title" => $user->user_login, 
                    "value" => $user->ID
                );
            }
        }
    }
     
    return $fields;
}