无法使用PHP刷新Facebook共享URL

I have a link to share, and Facebook's cache doesn't update when I update my link parameters.

I'm able to update it manually through this link: https://developers.facebook.com/tools/debug/og/object/

Simply, my code just doesn't work to do this:

$graph = 'https://graph.facebook.com/';
$post  = 'id=' . urlencode("http://fbooo.byethost4.com/committees/6") . '&scrape=true';
send_post($graph, $post);
function send_post($url, $post)
{
    $r = curl_init();
    curl_setopt($r, CURLOPT_URL, $url);
    curl_setopt($r, CURLOPT_POST, 1);
    curl_setopt($r, CURLOPT_POSTFIELDS, $post);
    curl_setopt($r, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($r, CURLOPT_CONNECTTIMEOUT, 5);
    $data = curl_exec($r);
    curl_close($r);
    return $data;
}

I don't get any errors. What am I missing?