Here is the my sample code:

const feildName = new Map();
  var numberOfCurlyWords = arrayOfAllCurlyBracesWords.length;

  for(var i = 0; i< numberOfCurlyWords;i++){

    for(var j = 0; j<cols;j++){
      
      // Logger.log(arrayOfAllCurlyBracesWords[i]); 
      // Logger.log(studentData[0][j] + "   First");

      if(arrayOfAllCurlyBracesWords[i].toLowerCase() == studentData[0][j].toLowerCase()){
        Logger.log(arrayOfAllCurlyBracesWords[i]); 
      Logger.log(studentData[0][j] + "Doneee");

      // Need to understand how to insert values in map in appscript
        Logger.log("studentData:- "+studentData[0][j]+" j:- "+j);
        feildName.set(studentData[0][j],j);
          Logger.log(feildName.entries());

      }

    }
  }

And here is the image of the output which I receive:

Can you please help me to figure out why is the map still empty and why is the map.set() functioning here and how can I make it work?