I can sucessfully group the output of a Repeatable Custom Content v2 datatype... as long as there is only one page. As soon as I add a sibling page, the output displays everything from all pages instead of just the one page.

What am I doing wrong?

<xsl:param name="currentPage"/>

<xsl:key name="sections" match="item" use="./data [@alias='section']" />

<xsl:template match="/">

<xsl:for-each select="$currentPage/articles/items/item [count(. | key('sections', ./data [@alias='section'])[1]) = 1]">
<xsl:value-of select="./data [@alias = 'section']"/><br />

<xsl:for-each select="key('sections', ./data [@alias='section'])">
<xsl:value-of select="./data [@alias = 'title']"/></span></strong><br />
</xsl:for-each>
</xsl:for-each>

</xsl:template>