[Solved]-Removing "Series" label on highcahrt-columnrange chart-Highcharts

the "series 4" comes because you did not specify a name for your series. usually it's a better idea to give a meaningful name than removing it. otherwise it could be confusing which data is the tooltip for.

for example:

series: [{
    name: 'tokyo',
    data: [7.0, 6.9, 9.5, 14.5, 18.2, 21.5, 25.2, 26.5, 23.3, 18.3, 13.9, 9.6]
}, {
    name: 'new york',
    data: [-0.2, 0.8, 5.7, 11.3, 17.0, 22.0, 24.8, 24.1, 20.1, 14.1, 8.6, 2.5]
}]