Why doesn't proxying with bindip work?

Question

PHP

hello fellows, I ran into such a misfortune, I took a proxy from the Internet, they work fine, but only for even better work I needed to enter my proxies there, I bought it, inserted it, it doesn’t work ...

$_bindip           = 'XXX.XXX.XXX.XXX : XxxX';


do
{
   $context = stream_context_create();
   if ( $_bindip != 'default') {
      $opts = array('socket' => array('bindto' => $_bindip));
      $context = stream_context_create($opts);
   }

   $_retry  = false;
   $_socket = @stream_socket_client(($_url_parts['scheme'] === 'https' && $_system['ssl'] ? 'ssl://' : 'tcp://') . $_url_parts['host']. ":". $_url_parts['port'], $err_no, $err_str, 30,STREAM_CLIENT_CONNECT, $context);

    if ($_socket === false)
    {
        show_report(array('which' => 'index', 'category' => 'error', 'group' => 'url', 'type' => 'internal', 'error' => $err_no));
    }

but for some reason he refused to work, what could be the problem?