telerik tabstrip controls are showing up in other tabs

I have 3 telerik tabs:

<telerik:RadTabStrip ID="tabStrip" runat="server" MultiPageID="multiPage" OnTabClick="tabStrip_TabClick">
            <Tabs>
                <telerik:RadTab runat="server" Text="Pending Invoices"      PageViewID="pendingInvoicesPageView">
                </telerik:RadTab>
                <telerik:RadTab runat="server" Text="Paid Invoices" PageViewID="paidInvoicesPageView">
                </telerik:RadTab>
                <telerik:RadTab runat="server" Text="My Payment Account" PageViewID="myPaymentAccountPageView">
                </telerik:RadTab>
            </Tabs>
</telerik:RadTabStrip>

with 3 page view:

    <telerik:RadMultiPage ID="multiPage" runat="server"
        <telerik:RadPageView ID="PageView1" runat="server">
        </telerik:RadPageView>
        <telerik:RadPageView ID="PageView2" runat="server">
        </telerik:RadPageView>
        <telerik:RadPageView ID="PageView3" runat="server">
        </telerik:RadPageView>
    </telerik:RadMultiPage>

Now, the contents of PageView1 is showing up in PageView2 and PageView3 after I added the below code:

    <telerik:RadAjaxManager ID="radAjaxManager" runat="server">
        <AjaxSettings>
            <telerik:AjaxSetting AjaxControlID="tabStrip">
                <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="tabStrip" />
                    <telerik:AjaxUpdatedControl ControlID="multiPage" />
                </UpdatedControls>
            </telerik:AjaxSetting>
            <telerik:AjaxSetting AjaxControlID="multiPage">
                <UpdatedControls>
                    <telerik:AjaxUpdatedControl ControlID="tabStrip" />
                    <telerik:AjaxUpdatedControl ControlID="multiPage" />
                </UpdatedControls>
            </telerik:AjaxSetting>
        </AjaxSettings>
    </telerik:RadAjaxManager>

Please give me an advise, i'm lost in this telerik control. TIA!