Photo upload always fails

    [System.Web.Mvc.HttpPost]
    public async Task<JsonResult> UploadListingImage()
    {
        String result = string.Empty;
        var files = Request.Form.Files; //Debug shows files is always null
        foreach (IFormFile sourceFile in files) //files is null so it does not go thru the loop
        {
            string FileName = sourceFile.Name + ".jpg";
            string imagepath = GetActualPath(FileName);

            try
            {
                if (System.IO.File.Exists(imagepath))
                {
                    System.IO.File.Delete(imagepath);
                }

                using (FileStream stream = System.IO.File.Create(imagepath))
                {
                    await sourceFile.CopyToAsync(stream);
                     result = "pass";
                }
            }
            catch (ArgumentNullException exp)
            {
                Console.WriteLine("Please provide a valid file path.");
            }
        }

        return Json(result); //once the loop is skipped the operation directly returns this one
    }