C# - Exchange Session Variables Between Webmethods In Webservices?

I have the following code to store session variable in one webmethod and retrieve it in other webmethod but the value displays null when i try to retrieve it.

[WebMethod(EnableSession = true)]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public bool SubmitList1(string businessname )
{
Session["Company_Name"] = businessname;
SqlConnection con = new SqlConnection();
.......
.........
.........
}

This will be my second webmethod where i am trying to retrieve the session variable

[WebMethod(EnableSession = true)]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public bool addresslisting()
{
string companyname = (string)Session["Company_Name"];// this particular value is displaying null
......
........
}