XTDE0160 : XSLT 1.0 compatibility mode is not available in this configuration in buil-in template rule for /invoice:request in the unnamed mode

I'm always with the same problem. I've allready created a question : Namespace prefix xsl on value-of is not defined. thanks to Michael for his answers. I saw all similar questions, but I found nothing to help me. I test my code with saxon9he and I try to group it with muenchian method. XML file :

<invoice:request xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:invoice="http://www.xmlData.ch/xmlInvoice/XSD" 
    xsi:schemaLocation="http://www.forum-datenaustausch.ch/invoice MDInvoiceRequest_400.xsd" role="production">

    <invoice:invoice invoice_id="22">
      <invoice:vat>0.00</invoice:vat>
      <invoice:record_tarmed>Rapport médical sur formulaire assurance-maladie</invoice:record_tarmed>
  </invoice:invoice>
    <invoice:invoice invoice_id="23">
      <invoice:vat>5.00</invoice:vat>
      <invoice:record_tarmed>Salle d'examen et de traitement, chirurgie et chirurgie pédiatrique</invoice:record_tarmed>
   </invoice:invoice> 
</invoice:request>

XSLT file :

<xsl:stylesheet version="1.0"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  xmlns:invoice="http://www.xmlData.ch/xmlInvoice/XSD"
  exclude-result-prefixes="invoice">

  <xsl:output method="xml" version="1.0" encoding="UTF-8" indent="yes"/>

  <xsl:key name="factures-par-TVA" match="invoice:invoice" use="invoice:vat"/>
  <xsl:template match="invoice:request">
    <Documents>
       <xsl:for-each select="invoice:invoice[count(. | key('factures-par-TVA', invoice:vat)[1]) = 1]">
          <xsl:sort select="invoice:vat" />
          <Document>
            <xsl:copy-of select="invoice:vat" />
            <xsl:for-each select="key('factures-par-TVA',invoice:vat)">
               <xsl:sort select="invoice:invoice/@invoice_id"/>
               <xsl:copy-of select="invoice:record_tarmed"/>
            </xsl:for-each>
          </Document>
        </xsl:for-each>
      </Documents>
    </xsl:template>
  </xsl:stylesheet>

The result is the same : error XTDE0160. If I remove 'invoice:' for 'request', the temp.html file contains the text of the 4 nodes and I get this warning SXXP0005 : the source document is in namespace http://www.xmlData.ch/xmlInvoice/XSD, but all the template rules match elements in no namespace.

I tried the mode attribute of xsl:template but it does'nt work.

what can I do ?

thanks for your help