MVC datetime2 ve nesne bulunamadı sorunu

KutuphaneEntities db = new KutuphaneEntities();
// GET: Odunc.
public ActionResult Index()
{
var degerler = db.tblHareket.Where(x => x.IslemDurum == false).ToList();
return View(degerler);
}
[HttpGet]
public ActionResult OduncVer()
{
List<SelectListItem> deger1 = (from x in db.tblUyeler.ToList()
select new SelectListItem.
{
Text = x.UyeAd + " " + x.UyeSoyad,
Value = x.UyeId.ToString()
}).ToList();

List<SelectListItem> deger2 = (from y in db.tblKitap.Where(x => x.Durum == true).ToList()
select new SelectListItem.
{
Text = y.KitapAd,
Value = y.KitapId.ToString()
}).ToList();

List<SelectListItem> deger3 = (from z in db.tblPersonel.ToList()
select new SelectListItem.
{
Text = z.PersonelAd + " " + z.PersonelSoyad,
Value = z.PersonelId.ToString()
}).ToList();
ViewBag.dgr1 = deger1;
ViewBag.dgr2 = deger2;
ViewBag.dgr3 = deger3;
return View();
}
[HttpPost]
public ActionResult OduncVer(tblHareket p)
{
var d1 = db.tblUyeler.Where(x => x.UyeId == p.tblUyeler.UyeId).FirstOrDefault();
var d2 = db.tblKitap.Where(y => y.KitapId == p.tblKitap.KitapId).FirstOrDefault();
var d3 = db.tblPersonel.Where(z => z.PersonelId == p.tblPersonel.PersonelId).FirstOrDefault();
p.tblUyeler = d1;
p.tblKitap = d2;
p.tblPersonel = d3;
db.tblHareket.Add(p);
db.SaveChanges();
return RedirectToAction("Index");
}
public ActionResult OduncIade(tblHareket p)
{
var odn = db.tblHareket.Find(p.HareketId);
DateTime d1 = DateTime.Parse(odn.IadeTarih.ToString());
DateTime d2 = Convert.ToDateTime(DateTime.Now.ToShortDateString());
TimeSpan d3 = d2 - d1;
ViewBag.dgr = d3.TotalDays;
return View("OduncIade", odn);
}
public ActionResult OduncGuncelle(tblHareket p)
{
var hrk = db.tblHareket.Find(p.HareketId);
hrk.UyeGetirTarih = p.UyeGetirTarih;
hrk.IslemDurum = true;
db.SaveChanges();
return RedirectToAction("Index");
}