Adding / Removing Session Variables On Page OnInit/OnLoad In C#?

I am using C#.

I am having below code in C#:

protected override void OnInit(EventArgs e)
{
try
{
if (Session["boolSignOn"].ToString() == "true".ToString())
{
lblPanelOpen.Text = Session["panelOpen"].ToString();
}
else
{
lblPanelOpen.Text = Session["panelOpen"].ToString();
}
}
catch (Exception ex)
{
Logger.Error("Error processing request:" + ex.Message);
}
}
protected override void OnLoad(EventArgs e)
{
try
{
if (!string.IsNullOrEmpty(Session["panelOpen"].ToString()))
{
lblPanelOpen.Text = string.Empty;
Session.Remove("panelOpen");
}
}
catch (Exception ex)
{
Logger.Error("Unable to remove the session variable:" + ex.Message);
}
}

In above code I am having a Session["panelOpen"] variable which is created from another user control and once my page is trying to render, I am storing Session["panelOpen"] in my hidden lblPanelOpen.Text on page OnInit() method, however when page is loaded completely then I am trying to remove the session variable.