Chartjs-Set stepSize for radar chart

Ticks object should be inside r

var options = {
          elements: {
            line: {
              borderWidth: 3
            }
          },
          scales: {
            r: {
              grid: {
                lineWidth: 4
              },
              angleLines: {
                lineWidth: 6
              },
              suggestedMin: 0,
              suggestedMax: 100,
              ticks: {
                stepSize: 20
              }
            }
          },             
        };