从PHP导出有趣的错误

An error in this code, for exporting it to excel. If not use line 1 and 2 code is working perfectly. If use line 1 and line 2 code it's working but don't export to excel, redirect to PHP control page. Also can see result there its normal. Where is the problem?

    $servis_listesi = mysql_query("SELECT * from servis_listesi");


    while($tumservisler = mysql_fetch_array($servis_listesi)){

    $ad_servis = $tumservisler["servis_adi"];
    $kod_servis = $tumservisler["servis_kodu"];
    $servisil = $tumservisler["servis_il"];  // line 1 
    $servisilce = $tumservisler["servis_ilce"];  // line 2

    $ortalamasi = mysql_query("select avg(anket_puani),COUNT(anket_puani) from anket_sonuclar where servis_kodu='".$kod_servis."' and anket_tarihi between '".$tarih1."' and '".$tarih2."'");
    $bicimle = mysql_fetch_array($ortalamasi);


    $sonuc_reel = $bicimle["avg(anket_puani)"];
    $sonuc_sayi = $bicimle["COUNT(anket_puani)"];

    $sonuc_net = round($sonuc_reel,2);


        echo '<tr>
                    <td>'.$kod_servis.'</td>
                    <td>'.$ad_servis.'</td>
                    <td>'.$servisil.'</td> <!-- line 1 want to use here-->
                    <td>'.$servisilce.'</td><!-- line 2 want to use here-->
                    <td>'.$sonuc_sayi.'</td> 
                    <th></th>
                    <td>'.$sonuc_net.'</td>


        </tr>';




    };
header("Content-Type: application/vnd.ms-excel");header('Content-Type: text/html; charset=utf-8');header("Content-disposition: attachment;filename='anket_list ".date('d.m.Y').".xls");

Hi Mahir if it is possible please try the give code below and check once. $tumservisler = mysql_fetch_array($servis_listesi); while($tumservisler){

}

Error is solved. I used the previous headers that is all. Thanks.