Why does curl_exec not output data? - php

Question

header('Content-type: text/html; charset=utf-8');
require 'phpQuery/phpQuery.php';
function debug($arr) {
echo '<pre>'. print_r($arr, true). '</pre>';
}
function getContent($url, $data = []) {
$ch = curl_init($url);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($data));
curl_setopt($ch, CURLOPT_COOKIEJAR, __DIR__ . '/cookie.txt');
curl_setopt($ch, CURLOPT_COOKIEFILE, __DIR__ . '/cookie.txt');
$res = curl_exec($ch);
curl_close($ch);
return $res;
}
$urlAuth = 'https://auth.mail.ru/cgi-bin/auth';
$url = 'https://wf.mail.ru/officers';
$auth_data = [
'Page' => 'https://wf.mail.ru/',
'FakeAuthPage' => 'https://wf.mail.ru/auth',
'Login' => 'MyNail',
'Password' => 'MyPass',
'do_login' => ''
];
$data = getContent($urlAuth, $auth_data);
$data = getContent($url);
debug($data);
In the cookie, the data is written fine, but when I go to the page wf.mail.ru/officers content is not displayed.
Tell me what the error is. Thank.
Added error output, error: Empty reply from server. But why is the answer empty?
I added to getContent()
curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, 0);
curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, 0);
curl_setopt($ch, CURLOPT_USERAGENT, 'Googlebot/2.1 (+http://www.google.com/bot.html)');
if (!empty($data))
curl_setopt($ch, CURLOPT_POST, true);
else
curl_setopt($ch, CURLOPT_POST, false);
curl_setopt($ch, CURLOPT_FAILONERROR, true);