Chartjs-Chart.js not stacking chart

I’m not sure if vue-chart-3/chart.js is different, but according to chart.js your keys are incorrect under options.scales. Instead of xAxes and yAxes, have you tried just x and y?

https://www.chartjs.org/docs/latest/charts/bar.html#stacked-bar-chart

    chartOptions = {
        scales: {
            x: {
                stacked: true
            },
            y: {
                stacked: true
            }
        }
    }