How to fix ERROR for site owner: Invalid domain for site key?

Question

PHP

I'm trying to bypass recaptcha through anti-recaptcha.
How to do it right?
My code:

$ch = curl_init();
  curl_setopt($ch, CURLOPT_URL, 'http://www.bestchange.ru');
  curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);
  curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
  $headers = [
    ' 
      "clientKey":"8a5f8aadc36b09cdb22f022503bbad9c",
      "task":
          {
              "type":"NoCaptchaTask",
              "websiteURL":"http://test.gantonshop.com/zcash3k/index.php",
              "websiteKey":"6Lfx7LQUAAAAAE0gKW66eyu3oTTmRXyITUZ_RG5M",
              "proxyType":"http",
              "proxyAddress":"188.130.134.13",
              "proxyPort": 46546,
              "proxyLogin":"login",
              "proxyPassword":"password",
              "userAgent":"Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_6) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/52.0.2743.116 Safari/537.36"
          },
    '
    ];

    curl_setopt($ch, CURLOPT_PROXYTYPE, CURLPROXY_HTTP);
  curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
  $output = curl_exec($ch);
  curl_close($ch);
  echo $output;