Скачивание файла с хостинга

Есть файл обработчик, который создает дамп БД на хостинге, но я не могу скачать его.

<?php
    if( isset( $_POST['dump'] ) )
    {

$server = "";//СЕРВЕР MYSQL
$user_db = "";//ЮЗЕР MYSQL
$pass_db = "";//ПАРОЛЬ MYSQL
$base_db = "";//ИМЯ_БАЗЫ MYSQL
$mysqli = new mysqli($server, $user_db, $pass_db, $base_db);     
$results = mysqli_query($mysqli,'SELECT user.id, user.login, user.mail, user_inf.f_name, user_inf.l_name, user_inf.b_date 
                                    FROM user JOIN user_inf ON user.id = user_inf.id
                                    ORDER BY user.id ASC');
while ($row = $results->fetch_assoc()) {
    $Array_for_dump['id'][]             = $row['id'];
    $Array_for_dump['login'][]          = $row['login'];
    $Array_for_dump['mail'][]           = $row['mail'];
    $Array_for_dump['f_name'][]         = $row['f_name'];
    $Array_for_dump['l_name'][]         = $row['l_name'];
    $Array_for_dump['b_date'][]         = $row['b_date'];
}
require_once('PHPExcel.php');
$phpexcel = new PHPExcel();
$titles = array (
    array (
            'name' => 'ID',
            'cell' => 'A'
        ),
    array (
            'name' => 'login',
            'cell' => 'B'
        ),
    array (
            'name' => 'mail',
            'cell' => 'C'
        ),
    array (
            'name' => 'f_name',
            'cell' => 'D'
        ),
    array (
            'name' => 'l_name',
            'cell' => 'E'
        ),
    array (
            'name' => 'b_date',
            'cell' => 'F'
        )
);
for( $i = 0; $i < count($titles); $i++){
    $string = $titles [$i]['name'];
    $cellLetter = $titles[$i]['cell'] . 1;
    $phpexcel->getActiveSheet()->setCellValueExplicit($cellLetter, $string, PHPExcel_Cell_DataType::TYPE_STRING);
}
$i = 2;
for ($j = 0; $j < count($Array_for_dump['id']); $j++){
    $phpexcel->getActiveSheet()->setCellValue("A$i", $Array_for_dump['id'][$j]);
    $phpexcel->getActiveSheet()->setCellValueExplicit("B$i", $Array_for_dump['login'][$j], PHPExcel_Cell_DataType::TYPE_STRING);
    $phpexcel->getActiveSheet()->setCellValueExplicit("C$i", $Array_for_dump['mail'][$j], PHPExcel_Cell_DataType::TYPE_STRING);
    $phpexcel->getActiveSheet()->setCellValueExplicit("D$i", $Array_for_dump['f_name'][$j], PHPExcel_Cell_DataType::TYPE_STRING);
    $phpexcel->getActiveSheet()->setCellValueExplicit("E$i", $Array_for_dump['l_name'][$j], PHPExcel_Cell_DataType::TYPE_STRING);
    $phpexcel->getActiveSheet()->setCellValueExplicit("F$i", $Array_for_dump['b_date'][$j], PHPExcel_Cell_DataType::TYPE_STRING);
    $i++;
}
$page = $phpexcel->setActiveSheetIndex();
$page->setTitle("Dump_DataBase");
$objWriter = PHPExcel_IOFactory::createWriter($phpexcel, 'Excel2007');
$filename = "Dump_DataBase.xlsx";
if ( file_exists($filename)) {
    unlink($filename);
}
$objWriter->save($filename);

  if (file_exists($filename)) {
    // сбрасываем буфер вывода PHP, чтобы избежать переполнения памяти выделенной под скрипт
    // если этого не сделать файл будет читаться в память полностью!
    if (ob_get_level()) {
      ob_end_clean();
    }
    // заставляем браузер показать окно сохранения файла
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename=' . basename($filename));
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($filename));


            $message = 'Successfully completed!';
            $color = 'green';
            $out = array(
                'message' => $message,
                'color' => $color
            );
            header('Content-Type: text/json; charset=utf-8');
            echo json_encode($out);
            die;
    }

?>