How to parse the value from xmlns?

Hi Guys,

I'm trying the parse the report content value from the below xml, but it's returning Null.

Could you please help me on this??

Query:

SELECT APEX_WEB_SERVICE.PARSE_XML (

P_XML => XMLTYPE(:VAL),

P_XPATH => '//reportBytes/text()',      

P_NS => 'xmlns:ns2="http://xmlns.oracle.com/oxp/service/PublicReportService"'

) VAL FROM DUAL

Xml:

<env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope">

 <env:Header/>

 <env:Body>

    <ns2:runReportResponse xmlns:ns2="http://xmlns.oracle.com/oxp/service/PublicReportService">

   <ns2:runReportReturn>

    <ns2:reportBytes>output</ns2:reportBytes>

    <ns2:reportContentType>text/xml</ns2:reportContentType>

        <ns2:reportFileID xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>

        <ns2:reportLocale xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>

        <ns2:metaDataList xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:nil="true"/>

   </ns2:runReportReturn>

  </ns2:runReportResponse>

 </env:Body>

</env:Envelope>