title: Creating excel file and writing to it with ExcelJS
body: <p>I wrote a script that creates a new excel file with ExcelJS. Adds 3 headers and inserts 2 rows. Then saves that file to disk. </p>
  
  <p>In the next step it should read that previously saved file, add 1 row and save it again under a new name. I can't find the reason why the second part where I try to add 3rd row never happens. Both files look the same and there are no errors in console. </p>
  
  <pre><code>const Excel = require('exceljs');
  
  async function exTest(){
    const workbook = new Excel.Workbook();
    const worksheet = workbook.addWorksheet("My Sheet");
  
  worksheet.columns = [
    {header: 'Id', key: 'id', width: 10},
    {header: 'Name', key: 'name', width: 32}, 
    {header: 'D.O.B.', key: 'dob', width: 15,}
  ];
  
  worksheet.addRow({id: 1, name: 'John Doe', dob: new Date(1970, 1, 1)});
  worksheet.addRow({id: 2, name: 'Jane Doe', dob: new Date(1965, 1, 7)});
  
  // save under export.xlsx
  await workbook.xlsx.writeFile('export.xlsx');
  
  // load a copy of export.xlsx
  const newWorkbook = new Excel.Workbook();
  await newWorkbook.xlsx.readFile('export.xlsx');
  
  const newworksheet = newWorkbook.getWorksheet('My Sheet');
  newworksheet.addRow(
    {id: 3, name: 'New Guy', dob: new Date(2000, 1, 1)}
  );
  
  await newWorkbook.xlsx.writeFile('export2.xlsx');
  
  console.log("File is written");
  };
  
  exTest();
  </code></pre>