Facebook cron工作上传每日照片给多个用户

我开发了一个faceinhole类型的小应用程序，每天上传一张照片到相册，并在照片上粘贴倒计时，直到活动当天。我试图实现每日上传和张贴到墙上的每一个用户我保存，但它似乎每次失败…应用程序请求离线访问和发布流。它保存access_token和用户id。当cron作业每天运行时，它会获得1或2次成功上传，然后得到505页未找到错误。这是我的代码。有什么想法如何改变这一点，以使其工作吗?

   $app_id = "XXXXXXXXXXXXXXXXXXXX";
   $app_secret = "XXXXXXXXXXXXXXXXXXXXXXXXX";

$sel=mysql_query("SELECT * FROM faceinhole WHERE imagen!='' AND activo=1");
while($as=mysql_fetch_array($sel)){
     $facebook = new Facebook(array(
    'appId' => $app_id,
    'secret' => $app_secret,
    'cookie' => true,
    'domain' => "mydomain.com"
    ));
    extract($as);
if(is_file($imagen)){
 $future=mktime(20,0,0,10,14,2011);
 $now = time();
 $timeleft = $future-$now;
 $daysleft=floor($timeleft/60/60/24);
 list($w,$h)=getimagesize($imagen); 
 $imagen2=imagecreatefromjpeg($imagen);
 imagepng($imagen2,$imagen.".png");
 $imagen3=imagecreatefrompng($imagen.".png");
 $color = imagecolorallocate($imagen3, 58, 221, 2);
 imagettftext ( $imagen3 , 64 , 0 , 124 ,315 , $color , "Gotham-Ultra.ttf" , "$daysleft" );
 $prefijo2 = substr(md5(uniqid(rand())),0,6);
 $connum="fotos/".$prefijo."_feis_num.png";
 imagepng($imagen3,$connum);
$facebook->setFileUploadSupport(true);
if($album_id!=""){
    $album_uid=$album_id;
    }else{
    $album_details = array(
    'access_token'  => "$access_token",
            'message'=> "Mis camisetas de los Juegos Panamericanos Guadalajara 2011. Viste la camiseta Panamericana para tu perfil de facebook aquí -> http://facebook.com/galeriasgdl?sk=app_$app_id",
            'name'=> 'Mis camisetas Panamericanas'
    );
    try{
$create_album = $facebook->api('/me/albums', 'post', $album_details);
    }catch(Exeption $e){
        }
$album_uid = $create_album['id'];
mysql_query("UPDATE faceinhole SET album_id='$album_uid' WHERE user_id='$user_id'")or die(mysql_error());;
}
$photo_details = array(
    'access_token'  => "$access_token",
    'message'=> "Estoy a $daysleft días de los Juegos Panamericanos Guadalajara 2011. Viste la camiseta Panamericana para tu perfil de facebook aquí -> http://facebook.com/galeriasgdl?sk=app_$app_id"
);
$file=$connum; 
$photo_details['image'] = '@' . realpath($file);
try{$upload_photo = $facebook->api('/'.$album_uid.'/photos', 'post', $photo_details);}catch(Exeption $e){}
}
}