I have the below file and send from ION API to M3

and I got this error in MEC

This the tag which I need to remove from the rcv file to solve this issue

Update:
I create a new mapping with the below code to remove the XML header
<xsl:stylesheet version="2.0" xmlns:xsl="">www.w3.org/.../Transform">
<xsl:output omit-xml-declaration="yes"/>
<xsl:template match="node()|@*">
<xsl:copy>
<xsl:apply-templates select="node()|@*"/>
</xsl:copy>
</xsl:template>
</xsl:stylesheet>
and send the output document "same document name" to the original mapping to override it and send correctly to MEC , but it failed ! I am still get the same error !