我无法使用以下代码向多个用户发送通知

Question

echo  $sql= "SELECT * from status WHERE name = '$name' AND leavefrom = '$leavefrom' AND leaveto = '$leaveto'";$result = mysqli_query($con,$sql);

while($row = mysqli_fetch_assoc($result)) { echo  $registrationIds = $row['token_id'];
$msg = array
      (
    'body'  => $_POST['body'],
    'title' => $_POST['title'],
            'icon'  => '',/*Default Icon*/
            'sound' => 'mySound'/*Default sound*/
      );
$fields = array
        (
            'to'        => $registrationIds,
            'notification'  => $msg
        );


$headers = array
        (
            'Authorization: key=' . API_ACCESS_KEY,
            'Content-Type: application/json'
        );


}

我无法使用上述代码向多个用户发送通知，它仅发送第一个用户通知。