Histogram 2d Visualization

Question

I'm testing plotly.js 2D Histogram contour to show the pressures of a foot, but it changes a lot the shape and it doesn't look like a foot pressure.

There is the Codepen to test it, as you can see these are 2 foot, one of them with a lot of missing data, but anyway I attach a picture from the Heat map to show you how I would like to show it, but with contours. On the Heat map the foot are inverted.

https://codepen.io/sebastcd/pen/OJEvpjW?editors=0010

These are the actual settings:

var trace2 = {
  x: x,
  y: y,
  name: 'density',
  ncontours: 20,
  colorscale: 'Hot',
  reversescale: true,
  showscale: false,
  type: 'histogram2dcontour',
  histfunc: 'sum',
  z: weights
};

Any ideas to don't change that much the shape and follow the "dots"?

Thanks