Requst.QueryString in aspx page

Hi All,
I have the following code in my aspx page.
<asp:Label id="lblCDR" runat="Server" text = '<%= Convert.ToString(Request.QueryString("CDR"))%>'></asp:Label> Although, Request.QueryString("CDR")) has value in it, but I am not getting any value on GUI side.
any help will be appreciated.