Label Text Not Changing

I have a label in a popupmodal that doesn't want to change. It does on my other pages in the same project.

<asp:Panel ID="Panel10" runat="server"><asp:Button ID="DummyButton" runat="server" Style="display: none" /><asp:ModalPopupExtender ID="Button1_ModalPopupExtender" runat="server" 
                                BackgroundCssClass="ModalBackgroud" CancelControlID="OKButton" Drag="True" 
                                DropShadow="True" DynamicServicePath="" Enabled="True" 
                                PopupControlID="pnlPopupWindow" TargetControlID="DummyButton"></asp:ModalPopupExtender><asp:Panel ID="pnlPopupWindow" runat="server" BorderStyle="None" 
                                CssClass="modalPopup"><asp:Panel ID="TitlePanel" runat="server" BackColor="White" 
                                    HorizontalAlign="Center" Width="100%"><asp:Image ID="TitlePanelImage" runat="server" Height="24" ImageAlign="Bottom" 
                                        ImageUrl="~/Images/info-icon.png" Width="24" /><asp:Label ID="lbTitlePanel" runat="server" Font-Bold="True" Font-Size="Large" 
                                        Font-Underline="False" Text="New Establishment"></asp:Label></asp:Panel><br /><asp:Label ID="lblMessage" runat="server"></asp:Label><asp:Panel ID="Panel3" runat="server" HorizontalAlign="Center"><br /><asp:Button ID="OKButton" runat="server" Text="OK" /></asp:Panel></asp:Panel></asp:Panel>

Code behind:

Dim message As String = "Please contact your agent or their supervisor at..." & vbCrLf  

lblMessage.Text = message         
Button1_ModalPopupExtender.Show()