In what conditions add_shown() Method won't work in jquery after the ModelPopupExtender shown?

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<asp:ModelPopoupExtender DialogBox  runat="server" ID="Dialog" Title="Carriage Charge" SaveButtonText="Apply" PopupDisplayMode="Normal"  CancelButtonUsePostBack="false" TitleIconUrl="/App_Themes/Theme/Icons/lorry_flatbed.png" >
    <MainContent >
        
        <script type="text/javascript">
        <!--
            $.pageLoaded(null, function () {
                console.log("Page Loaded Carriage Change");
                var CarriageDialogBox = $find('<%= Dialog.DialogBoxBehaviorID %>');
                if (CarriageDialogBox != null) {
                    console.log(CarriageDialogBox);
                    CarriageDialogBox.add_shown(function () {
                        console.log("Add Shown");
                        $("#<%= CarriageChargeDecimalTextBox.ClientID %>").focus();
                    });
                }
            });
        //-->
        </script>

        <fieldset style=" margin:0px; padding-removed5px; padding-removed20px; padding-removed20px;">
            <table width="100%" cellspacing="10" >
            <col width="120px" />
            <col />
                <tr>
                    <th><web:Label  runat="server" ID="CarriageChargeLabel" AssociatedControlID="CarriageChargeDecimalTextBox" Text="Carriage Charge" /></th>
                    <td><web:DecimalTextBox  runat="server" ID="CarriageChargeDecimalTextBox" AllowEmpty="false" Height ="20px" /></td>
                </tr>
            </table>
        </fieldset>
    </MainContent>
</asp:ModelPopoupExtender>

In above Jquery code I used console.log() method to debug in the console of the browser
This Method not invoke into and the Focus() Method also not invoke.
console.log("Add Shown");.

If there any other way to achieve the same thing , your suggestions are most welcome.