Error message 'adc' is an undeclared namespace - xslt-2.0

Question

All, am im relatively new to XSLT but did some solutions allready. Currently i am trying to write an xslt that moves a file to different folders based on if
<adc:Status>uploaded</adc:Status>
is "uploaded" or not.
Despite declasring the xmlns:adc Namespace i get the error
Exception Occured during TransForm using XSLT 2.0 (SaxonHe):
System.Xml.XmlException: 'adc' is an undeclared namespace. Line 2,
position 4.
I spent hours looking for the error messages, trying to getmyself into namespaces, but currently i cant seem to find out whats the cause of the error.
This is the xslt i wrote
<?xml version="1.0" encoding="ISO-8859-1"?>
<xsl:stylesheet version="2.0"
xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:adc="http://www.ifra.com/adconnexion/#v2"
xmlns:xs="http://www.w3.org/2001/XMLSchema"
exclude-result-prefixes="xs xsi adc">
<xsl:output method="xml" encoding="ISO-8859-1" indent="yes"/>
<xsl:template match="/">
<xsl:for-each select="/">
<xsl:variable name="Filename">
<xsl:value-of select="replace(document-uri(.), '.*/', '')"/>
</xsl:variable>
<xsl:choose>
<xsl:when test="/adc:adConnexion/adc:Requests/adc:AdOrder/adc:ProductionDetail/adc:Material/adc:Status='uploaded'">
<!-- Business case -->
<xsl:variable name="OutputFileName" select="concat('file:///C:\UPLOADED\',$Filename)"/>
<xsl:result-document href="{$OutputFileName}">
<xsl:copy-of select="current()"/>
</xsl:result-document>
</xsl:when>
<xsl:otherwise>
<!-- Non Business case -->
<xsl:variable name="OutputFileName" select="concat('file:///C:\ELSE\',$Filename)"/>
<xsl:result-document href="{$OutputFileName}">
<xsl:copy-of select="current()"/>
</xsl:result-document>
</xsl:otherwise>
</xsl:choose>
</xsl:for-each>
</xsl:template>
</xsl:stylesheet>
The simplified inputfile is
<adc:adConnexion xmlns:adc="http://www.ifra.com/adconnexion/#v2">
<adc:Requests>
<adc:AdOrder messageClass="BusinessTransaction" messageID="FEA*" bookingID="1234" messageCode="AD-O">
<adc:ProductionDetail>
<adc:Material>
<adc:Status>uploaded</adc:Status>
</adc:Material>
</adc:AdOrder>
</adc:Requests>
</adc:adConnexion>
Any help is greatly appreciated!