[Solved]-Multi series export is misaligned in highcharts-Highcharts

That issue is a Highcharts bug and it is reported here: https://github.com/highcharts/highcharts/issues/11509

As a workaround, you can set:

• height as a chart property:

    chart: {
        ...,
        height: 600
    },

or:

• height style directly on the container:

    document.getElementById('container').style.height = '600px';

Live demo: https://jsfiddle.net/BlackLabel/ot2fa94v/

API Reference: https://api.highcharts.com/highcharts/chart.height