使用Paypal进行PHP自适应支付：您的支付可以'；不可能完成。请返回参与网站并重试

我正在用自适应支付实现php代码，在最后一页的交易完成后，我得到一个错误，您的支付无法完成。请返回参与网站并重试。这个代码有什么问题。这是我的密码

enter code here
 <?php

 //turn php errors on
//ini_set("track_errors", true);

//set PayPal Endpoint to sandbox


$url = trim("https://svcs.sandbox.paypal.com/AdaptivePayments/Pay");




 $API_UserName = "s.patel_api1.sactp.ca"; //TODO
 $API_Password = "PA9YLDURHKTU52LH"; //TODO
 $API_Signature = "An5ns1Kso7MWUdW4ErQKJJJ4qi4-AOPwV4AdrC6q3hsN81pmNWMXn7f-"; //TODO
 $receiver_email = "rushi.mtech@gmail.com"; //TODO

 $amount = 25; //TODO

         //Default App ID for Sandbox    
     $API_AppID = "APP-80W284485P519543T";

 $API_RequestFormat = "NV";
 $API_ResponseFormat = "NV";




              $bodyparams = array (   "requestEnvelope.errorLanguage" => "en_US",
              "actionType" => "PAY",
              "cancelUrl" => "http://localhost/success.php",
              "returnUrl" => "http://localhost/cancel.php",
              "currencyCode" => "CAD",
              "receiverList.receiver.email" => $receiver_email,
              "receiverList.receiver.amount" => $amount
);

  // convert payload array into url encoded query string
   $body_data = http_build_query($bodyparams, "", chr(38));


try
{


      $params = array("http" => array(
    "method" => "POST",                                                 
    "content" => $body_data,                                             
    "header" =>  "X-PAYPAL-SECURITY-USERID: " . $API_UserName . "\r\n" .
             "X-PAYPAL-SECURITY-SIGNATURE: " . $API_Signature . "\r\n" .
             "X-PAYPAL-SECURITY-PASSWORD: " . $API_Password . "\r\n" .
             "X-PAYPAL-APPLICATION-ID: " . $API_AppID . "\r\n" .
             "X-PAYPAL-REQUEST-DATA-FORMAT: " . $API_RequestFormat . "\r\n" .
             "X-PAYPAL-RESPONSE-DATA-FORMAT: " . $API_ResponseFormat . "\r\n"
    ));


        //create stream context
        $ctx = stream_context_create($params);


      //open the stream and send request
        $fp = @fopen($url, "r", false, $ctx);

    //get response
     $response = stream_get_contents($fp);

       //check to see if stream is open
         if ($response === false) {
      throw new Exception("php error message = " . "$php_errormsg");
      }

            //close the stream
      fclose($fp);

 //parse the ap key from the response

     $keyArray = explode("&", $response);

      foreach ($keyArray as $rVal){
     list($qKey, $qVal) = explode ("=", $rVal);
       $kArray[$qKey] = $qVal;
     }
     $rushi;
  //print the response to screen for testing purposes
   If ( $kArray["responseEnvelope.ack"] == "Success") {

     foreach ($kArray as $key =>$value){
 // echo $key . ": " .$value . "<br/>";
    if($key == "payKey")
     {
    $rushi = $value;
    echo $rushi;
    }  
    }
    }
     else {
          echo 'ERROR Code: ' .  $kArray["error(0).errorId"] . " <br/>";
         echo 'ERROR Message: ' .  urldecode($kArray["error(0).message"]) . " <br/>";
           }   

      } 


     catch(Exception $e) {
      echo "Message: ||" .$e->getMessage()."||";
       }


?>

在此处输入代码

加上我的embaded html从请指导我