Answers for "TypeError: 'append' called on an object that does not implement interface FormData"

TypeError: 'append' called on an object that does not implement interface FormData

/*
Add processData
processData: false*/
$.ajax({
  url : "ajax/tmbpelanggan.php",
  type: "POST",
  data : { uploadExcel: true, uploadFiles: fd},
  processData: false,
  contentType: false,
  success:function(data, textStatus, jqXHR){
    console.log(data);
  },
  error: function(jqXHR, textStatus, errorThrown){
    console.log(textStatus);  
  }
});