[Solved]-Fix overlap on multiple stacked barchart-d3.js

Here's what I did different to your code.

Changed nv.models.multiChart() to nv.models.multiBarChart()

Updated chart to include :

.showControls(false)
.stacked(true);

Replaced the chart properties to the following :

chart.xAxis.tickFormat(d3.format(',f'));
chart.yAxis.tickFormat(d3.format(',.1f'));

//chart.xAxis.tickFormat(d3.format(',f'));
//chart.yAxis.tickFormat(d3.format(',.1f'));
//chart.yAxis2.tickFormat(d3.format(',.1f'));
//chart.bars1.stacked(true);
//chart.bars2.stacked(true);
//chart.bars1.groupSpacing(0.5);
//chart.bars2.groupSpacing(0.5);

You can find a working version of your code here

Hope it helps.