ebay api 2 finding item by keywords

<?php

error_reporting(E_ALL);

$endpoint = 'http://svcs.ebay.com/services/search/FindingService/v1';
$query = 'harry potter';

$filterarray =
	array(
		array(
			'name' => 'MaxPrice',
			'value' => '25',
			'paramName' => 'Currency',
			'paramValue' => 'USD'),
		array(
			'name'=> 'FreeShippingOnly',
			'value'=>'true',
			'paramName'=>'',
			'paramValue'=>''),
		array(
			'name'=>'ListingType',
			'value' => array('AuctionWithBIN','FixedPrice','StoreInventory'),
			'paramName' => '',
			'paramValue' => ''),
	);

function buildXMLFilter ($filterarray){
	global $xmlfilter;

	foreach ($filterarray as $itemfilter){
		$xmlfilter .= "<itemFilter>\n";

		foreach($itemfilter as $key => $value){
			if(is_array($value)){
				foreach($value as $arrayval){
					$xmlfilter .= " <$key>$arrayval</key>\n";
				}
			}
			else {
				if($value != ""){
					$xmlfilter .= " <$key>$value</$key>\n";
				}
			}
		}
		$xmlfilter .= "</itemFilter>\n";
	}
	return "$xmlfilter";
}

buildXMLFilter($filterarray);

$resp = simplexml_load_string(constructPostCallAndGetResponse($endpoint, $query, $xmlfilter));

if ($resp->ack == "Success"){
	$result = '';

	foreach($resp->searchResult->item as $item){
		$pic = $item->gallaryURL;
		$link = $item->viewItemURL;
		$title = $item->title;

		$results .= "<tr><td><img src=\"$pic\"></td><td><a href=\"$link\">$title</a></td></tr>";
	}
} else {
	$results = "<h3>Ops! The request was not successful. Make sure you are using a vlid ";
	$results .= "AppId for the Production environment.</h3>";
}

?>

<html>
<head>
<title>search result for <?php echo $query; ?></title>
<style type="text/css">
body {
	font-family:arial,sans-serif;
}
</style>
</head>
<body>
<h1>ebay search results for <?php echo $query; ?></h1>

<table>
	<tr>
	<td>
		<?php echo $results;?>
	</td>
	</tr>
</table>

</body>
</html>

<?php

function constructPostCallAndGetResponse($endpoint, $query, $xmlfilter){
	global $xmlrequest;

	$xmlrequest  = "<?xml version=\"1.0\" encoding=\"utf-8\"?>\n";
	$xmlrequest .= "<findItemsByKeywordsRequest xmlns=\"http:://www.ebay.com/marketplace/search/v1/services\">\n";
	$xmlrequest .= "<keywords>";
	$xmlrequest .= $query;
	$xmlrequest .= "</keywords>\n";
	$xmlrequest .= $xmlfilter;
	$xmlrequest .= "<paginationInput>\n <entriesPerPage>3</entriesPerPage>\n</paginationInput>\n";
	$xmlrequest .= "</findItemsByKeywordsRequest>";

	$headers = array(
		'X-EBAY-SOA-OPERATION-NAME: findItemsByKeywords',
		'X-EBAY-SOA-SERVICE-VERSION: 1.3.0',
		'X-EBAY-SOA-REQUEST-DATA-FORMAT: XML',
		'X-EBAY-SOA-GLOBAL-ID: EBAY-US',
		'X-EBAY-SOA-SECURITY-APPNAME: ',
		'Content-Type: text/xml;charset=utf-8',
	);

	$session = curl_init($endpoint);
	curl_setopt($session, CURLOPT_POST, true);
	curl_setopt($session, CURLOPT_HTTPHEADER, $headers);
	curl_setopt($session, CURLOPT_POSTFIELDS, $xmlrequest);
	curl_setopt($session, CURLOPT_RETURNTRANSFER, true);

	$responsexml = curl_exec($session);
	curl_close($session);
	return $responsexml;

}

?>

ebay search results for harry potter
Ops! The request was not successful. Make sure you are using a vlid AppId for the Production environment.

上手くいかない。。。
期待値は下記のようなインターフェイス