Google脚本无效分配左侧

好的，所以我有这段代码。抱歉，我不知道问题出在哪里，所以我全部粘贴了。它说：无效的分配在左侧。（第1行，文件“代码”）。我知道问题可能不在第一行，但不知道它在哪里。

function send(sheet, email, row){
  var tmp = GmailApp.getAliases();
  var alias = tmp[0];

  var subject = "Thank you for signing up for "+ sheet.getSheetName()+ "!";
  var body = "Hello "+ sheet.getRange(row,3).getValue() + " " + sheet.getRange(row,4).getValue() + "," + '\n'+'\n';
  var temp = 2;
  var bool = "TRUE";
  while (bool == "TRUE"){
    if (sheet.getRange(temp,11).getValue() != ''){
      body += '\n' + sheet.getRange(temp,11);
      temp += 1;
    }
    if (sheet.getRange(temp + 1,11).getValue() != '')
      body += '\n' + body += '\n' + sheet.getRange(temp + 1,11);
    else {bool = "FALSE"}
  }

  Logger.log(body);

  if ( sheet.getRange('L2').getValue() != ""){
    var html = sheet.getRange('L2').getValue();  // Place HTML code here
    try {
      GmailApp.sendEmail(email, subject, body, {'from': alias, 'htmlbody': html});
      sheet.getRange(row, 9).setBackground("green");
      sheet.getRange(row, 9).setValue("Yes");
      sheet.getRange("J2").setValue(row - 2);
    } catch (e) {
      var me = Session.getActiveUser().getEmail();
      MailApp.sendEmail(me, "Autoreply error", "There was a problem sending an email to: " + email +".");
    }
  }
  else{
    try {
      GmailApp.sendEmail(email, subject, body, {'from': alias});
      sheet.getRange(row, 9).setBackground("green");
      sheet.getRange(row, 9).setValue("Yes");
      sheet.getRange("J2").setValue(row - 2);
    } catch (e) {
      MailApp.sendEmail(me, "Autoreply error", "There was a problem sending an email to: " + email +".");
    }
  }
}

function main(){
  var ss = SpreadsheetApp.openById("1a2xvZ6hx69hst0CoLnCc8V5Igi-V5_HaNm6GTpEU8B4"); // Unique ID for the 'Responses' spreadsheet
  var sheet = ss.getActiveSheet();

  if ( sheet.getRange('J2').getValue() == "" ){
    sheet.getRange('I1').setValue("Sent");  // Initialize labels
    sheet.getRange('J1').setValue("Count");
    sheet.getRange('K1').setValue("Email body");
    sheet.getRange('L1').setValue("HTML body");
    var row = 2;
  } else {
    var row = sheet.getRange("J2").getValue() + 2;
  }
  while ( (sheet.getRange(row,9).getValue() != '') && (sheet.getRange(row,2).getValue() != '')) {
    var email = sheet.getRange(row, 2).getValue();
    send(sheet, email, row);
    row += 1;
  }
}