Пожалуйста, нужна ваша помощь! Я пытаюсь создать PHP-клиент мыла с curl. когда я запускаю свой код PHP. Я получил пустой результат. это соединение https. Я генерирую свой .pem файл с OpenSSL этимпример

PHP-код

    $xml = '<?xml version="1.0" encoding="utf-8"?>'.
        '<x:Envelope xmlns:x="http://schemas.xmlsoap.org/soap/envelope/" xmlns:req="http://olp.sadad.com/sadadpaymentmanagement/service/olppaymentmanager/req">'.
           '<x:Header/>'.
            '<x:Body>'.
        '<req:initiatePaymentDetailsReq>'.
           '<req:olpIdAlias>*****</req:olpIdAlias>'.
             '  <req:merchantId>*****</req:merchantId>'.
        '<req:merchantRefNum>999454564</req:merchantRefNum>'.
            '<req:paymentAmount>200</req:paymentAmount>'.
            '<req:paymentCurrency>SAR</req:paymentCurrency>'.
            '<req:dynamicMerchantLandingURL></req:dynamicMerchantLandingURL>'.
            ' <req:dynamicMerchantFailureURL></req:dynamicMerchantFailureURL>'.
              '</req:initiatePaymentDetailsReq>'.
              '</x:Body>'.
              '</x:Envelope>';
    try{
    $url = "https://b2brbtest.riyadbank.com/soap?service=RB_OLP_INITIATE_PAYMENT";
     $certFile =  dirname(__FILE__)."/key1.pem";
      $certPass = "*******";
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $url);
    curl_setopt($ch, CURLOPT_VERBOSE, true);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($ch, CURLOPT_SSL_VERIFYHOST, false);
    curl_setopt($ch, CURLOPT_SSLCERT, $certFile);
    curl_setopt($ch, CURLOPT_SSLCERTPASSWD, $certPass);
    $headers = array();
    array_push($headers, "Content-Type: text/xml; charset=utf-8");
    array_push($headers, "SOAPAction: sii:RB_OLP_INITIATE_PAYMENT");

    if($xml != null) {
        curl_setopt($ch, CURLOPT_POSTFIELDS, "$xml");
        array_push($headers, "Content-Length: " . strlen($xml));
    }

    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    $response = curl_exec($ch);
    $code = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);
    var_dump($response);

    }  catch (Exception $e){
    echo $e->getMessage();


    }

    ?>

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