Session values goes null in MVC controller

Question

hi,

I am working with mvc. my code is working fine till last day.But now i am facing an strange problem. I have set a value in Session. Here is code

[code] 

public ActionResult RecordForEdit(string ID)

{

int Idd = Convert.ToInt32(ID);

Session["SubuserId"] = Idd;

var model = new SubUserModel();

model.UserName = obd_Sub.LoginId;

model.Pwd = obd_Sub.Password;

model.Status = obd_Sub.Status;

return View("SubUserIndex", model);

}[/code]

 

then in view a method is called by Jquery .

[code]

public JsonResult GetAssigned_Suburb()

{

string UId ="";

if (Session["SubuserId"] != null)

{

UId = Session["SubuserId"].ToString();

}

var Suburbs = odbe.ODB_GetSuburb_onload(UId);

var jsonResult = Json(Suburbs.ToList(), JsonRequestBehavior.AllowGet);

return jsonResult;

}

[/code]

in this method i get the value of Session["SubuserId"], then again on a button click a method is called. 

 

[code]

public JsonResult GetSuburb_ToAssign(string Pcode, string SubId)

{

string UId = Session["UserId"].ToString();

var UsrId = from s in odbe.ODB_UserMain where s.LoginId == UId select s;

string intId = UsrId.FirstOrDefault().Id.ToString();

string sub_Uid = "0";

if (Session["SubuserId"] != null)

{

sub_Uid = Session["SubuserId"].ToString();

}

var Suburb = odbe.ODB_GetSubuserSuburb_Count(Pcode, intId, sub_Uid);

var jsonResult = Json(Suburb.ToList(), JsonRequestBehavior.AllowGet);

return jsonResult;

}

[/code]

But in this method the method the value of Session["SubuserId"] is null. I not get how it is gone null. I have debug and googled alot but nothing found.