Issue with XSL for website sitemap XML

The XSL for a website sitemap is not working as expected.

The URL elements are not being looped through?

Please can you take a look:

XML:

http://www.telephonesystems.co.uk/sitemap.xml

XSL:

http://www.telephonesystems.co.uk/css/sitemap.xsl

Thanks

Just change:

<xsl:stylesheet
  version="2.0"
  xmlns:html="http://www.w3.org/TR/REC-html40"
  xmlns:sitemap="http://www.sitemaps.org/schemas/sitemap/0.9"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform">

to:

<xsl:stylesheet
  version="2.0"
  xmlns:html="http://www.w3.org/TR/REC-html40"
  xmlns:sitemap="http://www.google.com/schemas/sitemap/0.9"
  xmlns:xsl="http://www.w3.org/1999/XSL/Transform">