saxonjs ignores match rules for json input

I'm trying to convert a json input into xml by using saxonjs, this is a simplified version of my code

const fs = require('fs');
const saxonJS = require('saxon-js');
const input = JSON.stringify({issue: {id: 'A001', number: 200 }});


saxonJS.transform({
        stylesheetLocation: './issues.sef.json',
        sourceType: 'json',
        sourceText: JSON.stringify(input),
        destination: 'serialized'}, 'async').then(data => {
        console.log(data.principalResult);
              res.status(200).send('Ok');
        }); 

        
    })
    .catch(err => {
        console.log(err);
        res.status(500).send('error');
    });

My xslt stylesheet is like this:

<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
    <xsl:output method="xml" encoding="utf-8" indent="yes"/>
    <xsl:template match="/">
        <Issue xmlns="urn:mycompany:2021">
        </Issue>
    </xsl:template>
</xsl:stylesheet>

The result is always empty or more precisely <?xml version="1.0" encoding="utf-8"?> If I replace match="/" with match="issue" or "/issue" the result is the same, what am I doing wrong?

/ matches a document node or document fragment node, your item is not a node but an XPath 3.1 map, use match="." to match any item, match=".[. instance of map(*)]" to match any map item.