上午图表项目符号重叠

如何解决上午图表项目符号重叠

如图所示有 2 个正方形（150 y 轴）重叠，我想分别显示它们，我该怎么做？

这里是代码方块：

var diaGraph = new AmCharts.AmGraph();
    diaGraph.valueAxis = bpValueAxis;
    diaGraph.valueField = "diastolic";
    diaGraph.balloonText = "DIA:[[diastolic]] "+uom+"<br><p style='font-size:9px;max-width:300px; word-wrap: break-word;'>[[alert_text]]</p>";
    diaGraph.colorField = "bullet_color";
    diaGraph.lineColor = "#808080";
    diaGraph.bullet = "square";
    chartBP.addGraph(diaGraph);