Ajax call not happening in first click

[Najmuddin Tasnim]

Hi,

I am using RadTreeView and RadAjaxManager on my page. Below is the code for ajaxifying the code
<telerik:AjaxSetting AjaxControlID="btnAdd">
            <UpdatedControls>
                <telerik:AjaxUpdatedControl ControlID="tvwSource" LoadingPanelID="RadAjaxLoadingPanelDisplay"/>
                <telerik:AjaxUpdatedControl ControlID="tvwTarget" LoadingPanelID="RadAjaxLoadingPanelDisplay"/>
            </UpdatedControls>
</telerik:AjaxSetting>

When I click on "Add" button for the first time on the page, there is a post back happening and then for the rest of the attempts I can see the Ajax callback and also the Loading Panel Id.

Am I missing anything?

Regards,
Najmuddin