[Solved]-Highcharts sankey diagram node rearrangement-Highcharts

The problem is related to this reported issue on Highcharts GitHub: https://github.com/highcharts/highcharts/issues/8218

As a workaround, you can call reflow after a chart is loaded.

    chart: {
        events: {
            load: function() {
                this.reflow();
            }
        }
    }

Live demo: https://jsfiddle.net/BlackLabel/vdLy2a0z/

API Reference: https://api.highcharts.com/class-reference/Highcharts.Chart#reflow