TypeError: Cannot read properties of undefined (reading 'source') onEdit@ Code.gs:2

function onEdit(e) {

  const sheet = e.source.getActiveSheet();

  const checkboxColumn = 18; 

  if (sheet.getName() === "Form Responses 1" && e.range.getColumn() === checkboxColumn) {

    if (e.range.isChecked()) {

      const entryRow = e.range.getRow();

      const sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Form Responses 1");

    const info = {

    'Timestamp': [rowData[1]],

    'Email Address': [rowData[2]],

    'What Happened ?': [rowData[3]],

    'Why is it a Problem ?': [rowData[4]],

    'Who Detected /  Who is Affected ?': [rowData[5]],

    'Where is the Problem ?': [rowData[6]],

    'When Detected ?': [rowData[7]],

    'How was it Detected': [rowData[8]],

    'How Many ?': [rowData[9]],

    'Part Number ': [rowData[10]],

    'Type of the component ': [rowData[11]],

    'Camera Stage': [rowData[12]],

    'Quantity to be blocked by PN': [rowData[13]],

    'Proposed disposition plan': [rowData[14]],

    'Due Date ': [rowData[15]],

    'Comment': [rowData[16]]

  };

      const pdfFile = createPDF(info);

      sheet.getRange(entryRow, 20).setValue(pdfFile.getUrl());

      sendEmail(info["Email Address"][0], pdfFile);

    }

  }

}