Appscript send mailmerge + PDF File data doesnt change

I tried to email invoices to customers as PDF file with appscript. Here is my function :

function sendPDF() {

  var data = getBody("DATA");
  var emailData = rowsToObjects(data);

  emailData.forEach(function (rowObject) {

  rincianTemplate(rowObject)

  DocumentApp.getActiveDocument();
  DriveApp.getFiles();

  const ss = SpreadsheetApp.getActiveSpreadsheet();
  const url = 'https://docs.google.com/spreadsheets/d/SS_ID/export?'.replace('SS_ID', ss.getId());
  const exportOptions =
    'exportFormat=pdf&format=pdf' + // export as pdf
    '&size=3.59x4.48' + //A3/A4/A5/B4/B5/letter/tabloid/legal/statement/executive/folio
    '&portrait=true' + // orientation portal, use false for landscape
    '&scale=3' + //1= Normal 100% / 2= Fit to width / 3= Fit to height / 4= Fit to Page
    '&top_margin=0' +
    '&bottom_margin=0' +
    '&left_margin=0' +
    '&right_margin=0' +   
    '&sheetnames=false&printtitle=false' + // hide optional headers and footers
    '&pagenumbers=false&gridlines=false' + // hide page numbers and gridlines
    '&fzr=false' + // do not repeat row headers (frozen rows) on each page
    '&gid=1720281854'; // the sheet's Id. Change it to your sheet ID.
  // You can find the sheet ID in the link bar. 
  // Select the sheet that you want to print and check the link,
  // the gid  number of the sheet is on the end of your link.
  
  var params = {method:"GET",headers:{"authorization":"Bearer "+ ScriptApp.getOAuthToken()}};
  var response = UrlFetchApp.fetch(url+exportOptions, params).getBlob();
  var templateData = getData("TEMPLATE");
  var emailSubjectTemplate = templateData[1][0]; //Cell A2
  var emailBodyTemplate = templateData[4][0]; //Cell A5
  
  var subject = renderTemplate(emailSubjectTemplate, rowObject);
  var body = renderTemplate(emailBodyTemplate, rowObject);
  var email = rowObject['EMAIL'];
      
      MailApp.sendEmail(email, subject, body, {
            htmlBody: body,
            attachments: [{
            fileName: "RINCIAN TAGIHAN.pdf",
            content: response.getBytes(),
            mimeType: "application/pdf"
        }]
    } 
  );
});
}

The function works well exceipt for the Invoices PDF send the same data (1st listed customer's invoice) to all listed customers. Please enlighten me :)