Apps Script to Create TXT Files Based on Data in Rows - export

Question

I am working through the following script which reads the data in certain rows and columns (from Cell A29 to Cell K150) and produces txt files based on data in Columns A and B. That is, if columns A and B have same items, only 1 file is produced with all data in those rows. The only problem is that the script also reads the blank rows/columns and creates a blank txt file. How can I modify the script to exclude blank rows (For example, data is in rows 29 - 100, I want the script to exclude remaining 50 rows and NOT create any files for blank rows)?
function CreateUploadFiles() {
// Retrieve values from Spreadsheet.
var sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("Summary"); //Set your sheet name.
var [, ...values] = sheet.getRange(28, 1, 150, 11).getValues();
// Create an array.
var csvBalanceArray = [...values.reduce((m, [h1, h2, ...r]) => {
var h = h1 + h2;
var temp = r.map(e => e instanceof Date ? Utilities.formatDate(e, Session.getScriptTimeZone(), "d/MM/yyyy") : e);
var name = `${h1} ${h2}`;
if (h2 == "Balance") {temp = temp.slice(0,3)}
return m.set(h, m.has(h) ? { rows: [...m.get(h).rows, temp], name } : { rows: [temp], name });
}, new Map()).values()];
console.log(csvBalanceArray)
//strip out new lines with space
// Create text files.
// var folder = DriveApp.getFolderById('J3'); // Set your folder ID.
var ss = SpreadsheetApp.getActive(); //Extracting Folder ID from Cell
var folder = ss.getRange("Summary!J3").getValue();
var destinationFolder = DriveApp.getFolderById(folder)
var files = destinationFolder.getFiles();
var GL = sheet.getRange("B2").getValue()
var period = sheet.getRange("B3").getValue()
var FY = sheet.getRange("B4").getValue()
//while (files.hasNext()) files.next().setTrashed(false); //For deleting files already created in your folder
csvBalanceArray.forEach(({ rows, name }) => destinationFolder.createFile(`P${period} FY${FY} ${GL} ${name}.txt`,
rows.map(r => r.join("***") //Join all columns to string value for each row
// replace remove all tab from new lines
.replaceAll("\t"," ").replaceAll("\n"," ").replaceAll("***","\t")).join("\n")));
}