Custom Class To Store The Properties And To Pass Its Instance Across The Pages

I've a requirement where i need to pass some objects across the pages. So i created a custom class with all the properties required and created a instance of it and assigned all the properties appropriately. I then put that object in the session and took it the other page. The problem is that even when i set the properties values to the class it is coming as null. I set a breakpoint in the getter-setter and saw that the value itself is coming as null.

public class GetDataSetForReports
{
private Table m_aspTable;
private int m_reportID;
private string m_accountKey;
private string m_siteKey;
private string m_imUserName;
/// <summary>
/// Asp Table containing the filters
/// </summary>
public Table aspTable
{
get
{
return m_aspTable;
}
set
{
m_aspTable = aspTable;
}
}
/// <summary>
/// Report ID
/// </summary>
public int reportID
{
get
{
return m_reportID;
}
set
{
m_reportID = reportID;
}
}
/// <summary>
/// All the accounts selected
/// </summary>
public string accountKey
{
get
{
return m_accountKey;
}
set
{
m_accountKey = accountKey;
}
}
/// <summary>
/// All the sites selected
/// </summary>
public string siteKey
{
get
{
return m_siteKey;
}
set
{
m_siteKey = siteKey;
}
}
/// <summary>
/// Current User Name
/// </summary>
public string imUserName
{
get
{
return m_imUserName;
}
set
{
m_imUserName = imUserName;
}
}
}

This is how i'm creating an instance in the page1 and trying to get it in the page2. Page1 Code

//Add the objects to the GetDataSetForReports Class
GetDataSetForReports oGetDSForReports = new GetDataSetForReports();
oGetDSForReports.aspTable = aspTable;
oGetDSForReports.reportID = iReportID;
oGetDSForReports.accountKey = AccountKey;
oGetDSForReports.siteKey = Sitekey;
oGetDSForReports.imUserName = this.imUserName.ToString();

But the values are not getting set at all. The values are not passing to the class (to the setter) at all. Am i making any OOP blunder?