Grouped Bar Chart not showing

I’m trying to plot a grouped bar chart adding traces dynamically from JSON data.

From the console.log it appears that the data passed to the chart is correctly formed.

Something like this for every trace:

{x: ["00:00 - 04:00", "04:00 - 08:00", "08:00 - 12:00","12:00 - 16:00", "16:00 - 20:00", "20:00 - 24:00"],
 y: [20, 14, 23,12, 18, 29],
 name: '1', 
 type: 'bar'
}

The chart is not showing but I’m not getting any error from the console.

These are my javascript functions (I took the filter function from this answer https://bit.ly/3jmISBP):

function _filter(list, predi) {
    let newList = [];
    for (let i = 0; i < list.length; i++) {
        if (predi(list[i])) newList.push(list[i]);
    }
    return newList;
}


function addChartData(data){    
    const uniqueLabels = [1,2,3,4]

    var traces = []
    
    for (let label of uniqueLabels) {

        x_axis = [];
        y_axis = [];
        labels = [];

        let filteredList= _filter(data, (traceData) => traceData.level == label);       
        
        for (let item of filteredList) {
            x_axis.push(item.fascia_oraria);
            y_axis.push(item.tempo_medio);
            labels.push(item.bin_level);
        }
        
        traces.push({
            x: x_axis,
            y: y_axis,
            /*text: labels,*/
            name: "Level " + label,
            type: "bar"
        });
    }

    var data = traces;

    var layout = {
        barmode: "group",
        showlegend: true,
    };

    Plotly.newPlot('myChart', data, layout);
}



function getAPIData(){
    $.ajax({
        method: 'GET',
        url: "../api/data",
        beforeSend: function(){
            $("#no_results").html("Loading data...");
        },
        success: function (data) {            
            addChartData(data);
        },
        error: function (data) {
            console.log('Error');
        }
    });
}

And calling the function from HTML like this:

<script>

  $(document).ready(function() {
    getAPIData();
  });

</script>

This approach worked for a simple bar chart, but not in this case.

Any idea about what I’m doing wrong?

Thank you