Formdata empty on Controller even after calling append - ajax

Question

On browse button click I have appended file(images) in FormData
and on Add Product button click I have to post Formdata via ajax to controller
but I am getting FromData as null on controller as well as on console.log.
Please let me know where I am going wrong.
Browse Button Click Event
$(document).ready(function () {
var _formData = new FormData();
$('.Btn_Browse').on('click', function () {
let input = document.createElement('input');
input.setAttribute('id', 'input_image')
input.setAttribute('multiple', 'multiple');
input.type = 'file';
input.onchange = _ => {
let files = Array.from(input.files);
if (files.length > 1) {
for (var i = 0; i < files.length; i++) {
_formData.append(files[i].name, files[i]);
}
};
input.click();
});
});
Add Product Button Click Event
$('#id_AddProduct').click(function (e) {
for (var key of _formData.entries()) {
console.log(key[0] + ', ' + key[1]);
}
$.ajax({
type: "POST",
url: "AddProduct",
contentType: false,
processData: false,
cache: false,
data: _formData,
success: function (response) {
},
failure: function (response) {
confirm("Your process is failed..");
},
error: function (response) {
confirm("Error occur during the process..");
}
});
});
Controller
public ActionResult AddProduct()
{
byte[] imagebyte = null;
int count = Request.Files.Count;
HttpFileCollectionBase Files = Request.Files;
for (int i = 0; i < Files.Count; i++)
{
HttpPostedFileBase httpPostedFileBase = Files[i];
if (httpPostedFileBase != null)
{
List<DALImage> imageList = new List<DALImage>();
if (Request.Files.Count > 0)
{
using (var br = new BinaryReader(httpPostedFileBase.InputStream))
{
var imgdata = br.ReadBytes(httpPostedFileBase.ContentLength);
DALImage objImg = new DALImage();
objImg.ImageName = httpPostedFileBase.FileName;
objImg.ImageTye = httpPostedFileBase.ContentType;
objImg.ImageData = Convert.ToBase64String(imgdata);
imageList.Add(objImg);
}
}
}
//string message = DAL.AddProduct(imageList, objProductDetails);
}
return Json(imagebyte, JsonRequestBehavior.AllowGet);
}