无法从Unocoin Public API获取数据

Question

我正在使用cURL从Unocoing的这个链接获取数据 - https://www.unocoin.com/trade?all

function api_price($api_url){
    if(!empty($api_url)){
$curl = curl_init();
curl_setopt_array($curl, array(
  CURLOPT_URL => $api_url,
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "GET",
));

$response = curl_exec($curl);
$err = curl_error($curl);
return $response;
curl_close($curl);
    }
}
if(!empty($_GET['url'])){ 
$api_url=$_GET['url'];
$tag=$_GET['tag'];
$api_price=api_price($api_url);
        $response = json_decode($api_price, true); 
       $output= $response[$tag];
        echo $output['lastPrice'];

}

我在其他交易所使用相同的代码。但有些像unocoin，coindelta显示bool（假） https://coindelta.com/api/v1/public/getticker/