MVC Import .csv - asp.net-mvc

Question

Controller
[HttpPost]
public ActionResult Import(HttpPostedFileBase excelFile)
{
if (excelFile == null || excelFile.ContentLength == 0)
{
ViewBag.Error = "Please select a excel file<br>";
return View("Index");
}
else
{
if (excelFile.FileName.EndsWith("xls") || excelFile.FileName.EndsWith("xlsx") || excelFile.FileName.EndsWith("csv"))
{
string fileName = Path.GetFileName(excelFile.FileName);
string path = Path.Combine(Server.MapPath("~/Content"), fileName);
//string path = Server.MapPath("~/Content/" + excelFile.FileName);
if (System.IO.File.Exists(path))
System.IO.File.Delete(path);
excelFile.SaveAs(path);
//Read data from excel file
MExcel.Application application = new MExcel.Application();
MExcel.Workbook workbook = application.Workbooks.Open(path);
MExcel.Worksheet worksheet = workbook.ActiveSheet;
MExcel.Range range = worksheet.UsedRange;
List<PH> publicholidays = new List<PH>();
for (int row = 0; row <= range.Rows.Count; row++)
{
PH ph = new PH();
ph.Subject = ((MExcel.Range)range.Cells[row, 1]).Text;
ph.StartDate = ((MExcel.Range)range.Cells[row, 2]).Text;
ph.EndDate = ((MExcel.Range)range.Cells[row, 4]).Text;
publicholidays.Add(ph);
}
ViewBag.Publicholidays = publicholidays;
return View("Success");
}
else
{
ViewBag.Error = "Incorrect file type<br>";
return View("Index");
}
}
}
I want to import a .csv file but why doesn't it work while when i try to import a normal .xls files, it works? Is there something wrong with my code or is it that I can't import .csv files this way?