雷达图缺少线条问题echarts radar配置项内容和展示

超过8项时出现如图问题，缺少2条分割线

      option = {
    title: {
        text: '体质测试'
    },
    tooltip: {},
    radar: {
        // shape: 'circle',
        splitNumber: 3,
        name: {
            textStyle: {
                color: '#F7F7F7',
                backgroundColor: '#999',
                borderRadius: 3,
                padding: [3, 5]
           }
        },
        splitArea: {
            areaStyle: {
                color: ['#B8D3E4', '#96C5E3', '#7DB5DA']
            }
        },
        axisLine: {
            lineStyle: {
                color: 'rgba(255, 255, 255, 1)'
            }
        },
 
        indicator: [
           { name: '平和质', max: 6},
           { name: '气虚质', max: 6},
           { name: '阳虚质', max: 6},
           { name: '阴虚质', max: 6},
           { name: '痰湿质', max: 6},
           { name: '湿热质', max: 6},
           { name: '血瘀质', max: 6},
           { name: '气郁质', max: 6},
           { name: '特禀质', max: 6}
        ]
    },
    series: [{
        type: 'radar',
        data : [
            {
                value : [1, 2, 3, 4, 5, 4,1,2,3]
            }
        ]
    }]
};