Ajax.BeginForm send parameters to controller

I have following Ajax.BeginForm on viewpage

using (Ajax.BeginForm("Financing_Product_Feature_Upload", "FileUpload", new { productid = @ViewBag.Product_ID }, new AjaxOptions() { HttpMethod = "POST" }, new { enctype = "multipart/form-data"}))
{
    @Html.AntiForgeryToken()
    <input type="file" name="files">   <input type="submit" value="Upload File to Server">
}

then I have following controller method in FileUpload controller class

[HttpPost]
public ActionResult Financing_Product_Feature_Upload(HttpPostedFileBase file, string productid)
{

but once I click above submit button its not directing to Financing_Product_Feature_Upload controller method