Auto-populate a column with timestamp when a new row is added

Code.gs

function onEdit(e) {

  var row = e.range.getRow();
  var col = e.range.getColumn();
  if(col === 2 && e.source.getActiveSheet().getName() === "help_requests") {
    if(e.source.getActiveSheet().getRange(row, 1).getValue() == "") {
      e.source.getActiveSheet().getRange(row, 1).setValue(new Date()); 
    }
  }
}