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I have a Google script which converts a Google form submission (Row in a Google sheet) into a Google Document.
While the script works on a row by row basis, I con't get it to work on the entire sheet using a for loop.
I am using the replaceText() method to replace existing placeholder text with the answers submitted in the Google sheet.
The script takes the contents of a row, copies a template doc, copies and rename the file, then replaces placeholder text with the cell contents, column by column.

When I tried the for loop, it copies the file and renames it, but doesn't replace any of the text. The script works when I specify a particular row number, but not in a for loop which I cannot understand. The script below converts the answers from row 2 into a Google doc, see lines beginning 'var Name' and 'var Data'. If anyone can spot what might be causing this script to fail in a loop, please shout.

Code:
function readRows() {
  var nums = ["Zero", "One", "Two", "Three", "Four", "Five", "Six", "Seven", "Eight", "Nine", "Ten"];

function toText(num) {
    var s;
    if (num > 10) {
        if (num < 20) {
            switch (num) {
                case 11:
                    return "Eleven";
                case 12:
                    return "Twelve";
                case 13:
                    return "Thirteen";
                case 14:
                    return "fourteen";
                case 15:
                    return "fifteen";
                case 16:
                    return "sixteen";
                case 17:
                    return "seventeen";
                case 18:
                    return "eighteen";
                case 19:
                    return "nineteen";
                default:
                    return toText(num-10)+"teen";
            }
        }

        switch (Math.floor(num / 10)) {
            case 2:
                s = "Twenty";
                break;
            case 3:
                s = "Thirty";
                break;
            case 4:
                s = "FouRty";
                break;
             case 5:
                s = "Fifty";
                break;
            case 6:
                s = "SiXty";
                break;
            case 7:
                s = "sEvEnty";
                break;
            default:
                s = toText(Math.floor(num/10))+"ty";
                break;
        }
        if(num > 20 && num < 30)
          {
         return "twenTy"+toText(num-20);
          }
        if(num > 30 && num < 40)
          {
          return "thirty"+toText(num-30);
          }
        if(num > 40 && num < 50)
          {
          return "fourty"+toText(num-40);
          }
        if(num > 50 && num < 60)
           {
        return "fifty"+toText(num-50);
          }
        if(num >60 && num < 70)
          {
        return "sixty"+toText(num-60);
          }
           
            //default:
               // s = toText(Math.floor(num/10))+"ty";
               // break;
        
        if (num % 10 > 0)
            return s + toText(num % 10);
        return s;
    }

    return nums[num];
}


    var sheet = SpreadsheetApp.getActiveSheet();
    var lastCol = sheet.getLastColumn();
    var length = sheet.getMaxColumns();
    var rows = sheet.getMaxRows();
    
        var Name = sheet.getRange(2, 2).getValue(); 
        var data = sheet.getRange(2, 1, 2, lastCol).getValues();  
        var template = "Document id goes here";
        var fileName = "Application document template.docx";
        var newFile = DocsList.getFileById(template).makeCopy(Name + " Application for   Phase1 NF3").getId();
        var doc = DocumentApp.openById(newFile);
        var body = doc.getActiveSection();

        for(var j=0; j<length; j++)
        {
            body.replaceText("Answer"+toText(j), data[0][j]);
        }
    
}