Getting Results Of 2 Items In Querystring Using Two Different Sqldatasources

Hi, I'm using the following to send two items in the querystring over to the next page, where I can display tables based on them. Both querystrings appear fine in the URL. The first querystring works fine to single out the order specified by the orderid from the querystring, but I can't seem to get my other sqldatasource to show the userid (+contents of aspnet_users table) using the userid I passed in the querystring.

<asp:HyperLinkField DataNavigateUrlFields="OrderID,UserId" DataNavigateUrlFormatString="Copy of Orders.aspx?OrderID={0}&UserId={1}" DataTextField="OrderID, UserId" /> 
 
This is what I'm using to try and pick up the userid
 
    <asp:GridView ID="GridView3" runat="server" AutoGenerateColumns="False" DataSourceID="SqlDataSource3" DataKeyNames="UserId">
        <Columns>
            <asp:BoundField DataField="UserId" HeaderText="UserId" SortExpression="UserId" />
            <asp:BoundField DataField="UserName" HeaderText="UserName" SortExpression="UserName" />
        </Columns>
    </asp:GridView>

    <asp:SqlDataSource ID="SqlDataSource3" runat="server" ConnectionString="<%$ ConnectionStrings:ConnectionString2 %>"
        SelectCommand="SELECT [UserId], [UserName] FROM [aspnet_Users] WHERE UserId = @UserId">
        <SelectParameters>
            <asp:QueryStringParameter DefaultValue="UserId" Name="UserId" QueryStringField="UserId"
                Type="object" />
        </SelectParameters>
        </asp:SqlDataSource>