Just add a template rule that throws away the BankDetails:
<xsl:template mode="copy-no-ns" match="test:BankDetails"/>
Also, this is quite wrong:
<xsl:template match="test:Submission">
<xsl:element name="AddressDetails">
<xsl:copy-of select="*" />
<xsl:apply-templates mode="copy-no-ns" select="node()" />
</xsl:element>
</xsl:template>
The xsl:copy-of select="*" copies all children of the Submission, which you don't want. I would get rid of this rule and replace it with
<xsl:template match="/">
<xsl:apply-templates select="//test:AddressDetails"/>
</xsl:template>
The error you report looks like a red herring.
Michael Kay
http://www.saxonica.com/
Author, XSLT Programmer's Reference and XPath 2.0 Programmer's Reference