javascript - How to Redraw HighChart After Dropdown Value is selected -

i have drop down menu called info , want update highchart everytime user selects value through info menu.

here code:

$('#info').on('change', function() {    add_info(this.value);  }); 

the add_info() method gets data via ajax , how processing after getting response back:

if(chart=='stacked_chart'){      console.log(json.stringify(response));            var series = [{name:'coached',data:[]},{name:'non coached',data:[],stack: 'yes'},{name:'delta',data:[],stack: 'yes'}],           year, month, day;               for(var i=0; i<response.length;i++){                   var d = response[i].date.split(",");                 year = parsefloat(d[0]);                 month = parsefloat(d[1])-1; //date.utc method starts month 0-11                 day = parsefloat(d[2]);                 var coached = +(parsefloat(response[i].coached).tofixed(3));                  var non_coached = +(parsefloat (response[i].non_coached).tofixed(3));                 var delta = +(parsefloat (response[i].delta).tofixed(3));                  series[0].data.push([date.utc(year,month,day),coached]);                 series[1].data.push([date.utc(year,month,day),non_coached]);                 series[2].data.push([date.utc(year,month,day),delta]);                 console.log(date.utc(year,month,day));             }                    console.log(series);            if(series.length){             stacked_chart.useroptions.series = series;             var chart = new highcharts.chart(stacked_chart.useroptions);             console.log(chart.series[0].data[0].options);             console.log(chart.series[1].data[0].options);             console.log(chart.series[2].data[0].options);             }     } 

i can see brings new data doesn't redraw. have looked @ here couldn't redraw chart. ideas how reset chart every time user selects new value drop down?