Save XML file into FTP PI

Hi Experts,

I'm facing a little problem.

I need to save a xml file into a ftp.

The communication is already done and works perfectly.

My Payload, is send from ECC SAP via RFC, and is like that:

But the .xml saved in ftp when opened is like this:

<?xml version="1.0" encoding="UTF-8"?>

<ns1:MT_InvoiceToDescartes xmlns:ns1="http://www.brf.net/ediEurope/AperakToDescartes"><XML>&lt;?xml version=&quot;1.0&quot; encoding=&quot;iso-8859-1&quot;?&gt;

&lt;INVOICES&gt;

  &lt;Envelop&gt;

    &lt;senderId&gt;123456&lt;/senderId&gt;

    &lt;recipientId&gt;123457&lt;/recipientId&gt;

    &lt;controlNumber&gt;&lt;/controlNumber&gt;

    &lt;dateTime&gt;20150903091225&lt;/dateTime&gt;

    &lt;testIndicator&gt;1&lt;/testIndicator&gt;

    &lt;messageType version=&quot;1&quot;&gt;INVOICE&lt;/messageType&gt;

  &lt;/Envelop&gt;

&lt;/INVOICES&gt;</XML></ns1:MT_InvoiceToDescartes>

But what I realy need, is the file was only the data that is into <XML> and not converted, like this:

<?xml version="1.0" encoding="iso-8859-1"?>

<INVOICES>

  <Envelop>

    <senderId>123456</senderId>

    <recipientId>123457</recipientId>

    <controlNumber></controlNumber>

    <dateTime>20150903091225</dateTime>

    <testIndicator>1</testIndicator>

    <messageType version="1">INVOICE</messageType>

  </Envelop>

</INVOICES>

I Need to do something in the Message Mapping or configure something more in the Channel Communication File?

I read some discusions, but I don't know what is applied to my case.

Thanks in advance.