New to AppScripting. In the script below I have a spreadsheet that works but I created a button that copies the template workbook into a new spreadsheet in folder of google drive. The problem is with a different button that creats a new sheet in the workbook. The for loop doesn’t seem to be executing and it just tries to create a new sheet. The for loop is supposed to display a message if the sheet already exists.

function newSheet() {

const sourceWbId = '1AIauqZi0SQkKPlFqSbCyXinUep7bjCspEJnl5_ic6y4';
let wb = opener(sourceWbId);
let sheets = wb.getSheets();
   
  let source = SpreadsheetApp.getActiveSpreadsheet();
  let sheet = source.getSheetByName('Template');

  //var summary = source.getSheetByName('Shipping Summary');

  const date = new Date();
  //or use
  const dateDisplay = new Date().toLocaleDateString();

  const year = date.getFullYear();
  const month = date.getMonth()+1;
  const day = date.getDate();
  let today = `${month}/${day}/${year}`;

const sheetIgnore = [today];

let ui = SpreadsheetApp.getUi();
`

  for(i in sheets) {
   if(sheets[i].getSheetName() == today) {
      let buttonPushed = ui.alert('Error','This sheet aready exists. ' + dateDisplay,ui.ButtonSet.OK_CANCEL);
      if(buttonPushed == 'OK'){
        source.toast('Accepted');
        return;
      }
      else if(buttonPushed == 'CANCEL'){
        source.toast('Canceled Operation');
        return;
      }
   }
   Logger.log(sheets)
  }
    if(sheets !== today){
      sheet.copyTo(source).setName(today);
      let targetSheet = source.getSheetByName(sheetIgnore);
      targetSheet.getRange(1,6).setValue('Date:' + String.fromCharCode(10) + today);
      targetSheet.getRange(1,5).setValue(false);
      targetSheet.getRange(1,4).setValue('Completed Send Email');
    }
   
  

}