Requests from referer are blocked."

Requests from referer "" are blocked."I'm using YouTube API v3 search in my laravel application.

$params = array("part" => "snippet","q" => $term,"type" => "channel","maxResults" => $limit,"key" => env('YOUTUBE_KEY')        );        $curl_session = curl_init();        $curl_options = array(            CURLOPT_URL => 'https://www.googleapis.com/youtube/v3/search?'. http_build_query($params),            CURLOPT_RETURNTRANSFER => true,        );        curl_setopt_array($curl_session, $curl_options);        $response = curl_exec($curl_session);        curl_close($curl_session);        $response = json_decode($response, true);        return $response; 

The search should work as expected.