Undefined issue

Other

HTML

<link rel="stylesheet" href="https://s3.amazonaws.com/flexmonster/2.3/demo.css">
<script src="https://cdn.flexmonster.com/flexmonster.js"></script>
<button onclick="getData()">Print</button>

<div id="pivot-container">The component will appear here</div>

<div class="output" id="output"></div>

CSS

.output {
  width: 80%;
  height: 300px;
  margin-left: auto;
  margin-right: auto;
  padding: 20px;
  background: rgba(242, 242, 242, 1);
  font-family: Menlo, Monaco, "Courier New", Courier, monospace;
  white-space: pre;
  font-size: 16px;
  font-weight: 400;
  overflow-y: scroll;
  margin-top: 20px;
}

JavaScript

let pivot = new Flexmonster({
  container: "pivot-container",
  componentFolder: "https://cdn.flexmonster.com/",
  licenseFilePath: "https://cdn.flexmonster.com/jsfiddle.charts.key",
  toolbar: true,
  height: 260,
  report:  {
  "dataSource": {
    "type": "json",
    "data": [
      {
        "day": "Tue",
        "days": 1,
        "city": "A",
        "sales": 100
      },
      {
        "day": "Sun",
        "city": "B",
        "days": 2,
        "sales": 200
      },
      {
        "day": "Wed",
        "city": "C",
        "days": 3,
        "sales": 300
      },
      {
        "day": "Sat",
        "city": "D",
        "days": 4,
        "sales": 400
      },
      {
        "day": "Mon",
        "city": "E",
        "days": 5,
        "sales": 500
      },
      {
        "day": "Fri",
        "city": "F",
        "days": 6,
        "sales": 600
      },
      {
        "day": "Thu",
        "days": 7,
        "city": "G",
        "sales": 800
      }
    ],
    "mapping": {
      "day": {
        "type": "string",
        "caption": "Day"
      },
      "city": {
        "type": "string",
        "caption": "City"
      },
      "sales": {
        "type": "number",
        "caption": "Sales"
      },
      "days": {
        "type": "number",
        "caption": "Days"
      }
    }
  },
  "slice": {
    "expands": { "expandAll": true },
    "columns": [
      {
        "uniqueName": "[Measures]"
      },
      {
        "uniqueName": "day",
        "sortOrder": [
          "mon",
          "tue",
          "wed",
          "thu",
          "fri",
          "sat",
          "sun"
        ]
      },
      {
        "uniqueName": "days"
      },
      {
        "uniqueName": "city"
      }
    ],
    "measures": [
      {
        "uniqueName": "sales",
        "aggregation": "sum",
        "format": "sales"
      }
    ]
  },
  "options": {
    "grid": {
      "type": "classic"
    }
  },
  "formats": [
    {
      "name": "sales",
     ...