FCM发送通知，但声音未播放

Question

我想向Android发送通知。通知发送成功。但是，电话声音不起作用。我想在通过电话收到通知时给电话打电话。 这是我的代码：

 $token=$_POST['token'];
$doctor=$_POST['d_name'];
        $API_KEY = "AAAAVXABzCk:APA91bHVimlQAf6uRFc04YaX_JPMO5lN0NXcSVq0Q5W7uGU1iZnPEMR5crlIhEFkpjM2NGhF1bZRt5vfYdDyrt7OCqXmaUNKLOPhQ3ZxjW_R";
        $url = 'https://fcm.googleapis.com/fcm/send';
        $message= ['order_id' =>  'hello'];

    $notification = [
        'title' => 'Appointment Confirmation',
        'body' => $doctor.' is enabled your appointment. Please, open application.',
       
        ];
    $fields = array (
        "to" => 'fZ3Tx1hTR6Ca5ecJMM3SXi:APA91bGBzBNdGawDU5O-FKJrPmYDG9FvCInyUUvnEfyPAzsCgVeaJvlNM1SY9ZYtaLCtbVMNZdurvHQ1PyYgoJ2DBFK0GzWDHQ80P',
        'notification'      => $notification,
       
        'data'              => $message,
         'vibrate'=>'1',
        'sound'=>'default',
    );
    $fields = json_encode ( $fields );
    $headers = array (
        'Authorization: key=' . $API_KEY,
        'Content-Type: application/json'
    );

    $ch = curl_init ();
    curl_setopt ( $ch, CURLOPT_URL, $url );
    curl_setopt ( $ch, CURLOPT_POST, true );
    curl_setopt ( $ch, CURLOPT_HTTPHEADER, $headers );
    curl_setopt ( $ch, CURLOPT_RETURNTRANSFER, true );
    curl_setopt( $ch,CURLOPT_SSL_VERIFYPEER, false );
    curl_setopt ( $ch, CURLOPT_POSTFIELDS, $fields );

    $result = curl_exec ( $ch );

    curl_close ( $ch );
    echo $result;
 

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