Web Forms :: Page Not Redirecting To Previous Page Using Session?

protected void lblNVariz_Click(object sender, EventArgs e)
{
Session["Page"] = "~/Admin.aspx";
Response.Redirect("Admin/Bank-Data.aspx");
}

but when I click on link button it didn't redirect to Bank_data.aspx page it just refresh admin.aspx page

but when I change code Like below

protected void lblNVariz_Click(object sender, EventArgs e)
{
Response.Redirect("Admin/Bank-Data.aspx");
}

it redirect to Bank_data.aspx page.When I put session on it, it didn't worked...