php - amazon mws api - update product via feed submit, always respond sample result only?

I'm using amazon api php i had updated config file and also update feed type, below my xml feed

$feed = <<<EOD
<?xml version="1.0" ?>
<AmazonEnvelope xmlns:xsi="http://ift.tt/ra1lAU" xsi:noNamespaceSchemaLocation="amzn-envelope.xsd">
<Header>
<DocumentVersion>1.01</DocumentVersion>
<MerchantIdentifier>**********</MerchantIdentifier>
</Header>
<MessageType>Inventory</MessageType>
<Message>
<MessageID>1</MessageID>
<OperationType>Update</OperationType>
<Inventory>
<SKU>***********</SKU>
<Quantity>900</Quantity>
</Inventory>
</Message>
</AmazonEnvelope>
EOD;

I try to update quantity, which always provide sample xml feed response finally i got result

Service Response ============================================================================= SubmitFeedResponse SubmitFeedResult FeedSubmissionInfo 
    FeedSubmissionId string FeedType string 
    SubmittedDate 2015-08-23T09:13:37Z 
    FeedProcessingStatus string 
    StartedProcessingDate 2015-08-23T09:13:37Z 
    CompletedProcessingDate 2015-08-23T09:13:37Z ResponseMetadata 
    RequestId string ResponseHeaderMetadata:

Above answer came from sample xml file which's follwing,

<?xml version="1.0" encoding="UTF-8"?>
<SubmitFeedResponse xmlns="http://ift.tt/1qIBrE9">
  <SubmitFeedResult>
    <FeedSubmissionInfo>
      <FeedSubmissionId>string</FeedSubmissionId>
      <FeedType>string</FeedType>
      <SubmittedDate>string</SubmittedDate>
      <FeedProcessingStatus>string</FeedProcessingStatus>
      <!--Optional:-->
      <StartedProcessingDate>2008-09-28T18:49:45</StartedProcessingDate>
      <!--Optional:-->
      <CompletedProcessingDate>2014-09-18T16:18:33</CompletedProcessingDate>
    </FeedSubmissionInfo>
  </SubmitFeedResult>
  <ResponseMetadata>
    <RequestId>string</RequestId>
  </ResponseMetadata>
</SubmitFeedResponse>