i have inquiry form which gets open in modal popup extender. when i click on button to store data click event does not get fired
<asp:ModalPopupExtender ID="ModalPopupExtender_2" runat="server" BackgroundCssClass="modalBackground"
PopupControlID="Panel2" TargetControlID="btnPopUp2" CancelControlID="btnClose2">
</asp:ModalPopupExtender>
<asp:Panel runat="server" ID="Panel2" CssClass="modalPopup" align="center" Style="display: none">
<center>
<div class="outer_div">
<div class="inner_div">
<h1>
Institute Enquiry Form</h1>
</div>
<div>
<br />
<asp:Literal runat="server" Text=" Your enquiry sent successfully..." ID="ltrMsg2"
Visible="false"></asp:Literal>
<br />
<asp:Label ID="Label1" runat="server" Text="Fileds marked with * are mandatory"></asp:Label><br />
<br />
<table>
<tr>
<td>
<asp:TextBox runat="server" ID="txtFullName" CssClass="textbox"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender8" runat="server" TargetControlID="txtFullName" WatermarkText="* Full Name ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtEmailId" CssClass="textbox"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender9" runat="server" TargetControlID="txtEmailId" WatermarkText="* E-mail ID ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<asp:TextBox ID="TextBox3" runat="server" Text="+91" ReadOnly="true" CssClass="textbox"
Width="30px"></asp:TextBox>
<asp:TextBox runat="server" ID="txtMobileNum" CssClass="textbox" Width="172PX"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender10" runat="server" TargetControlID="txtMobileNum"
WatermarkText="* Mobile number ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtCityName" CssClass="textbox"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender11" runat="server" TargetControlID="txtCityName"
WatermarkText="City ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtStateName" CssClass="textbox"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender12" runat="server" TargetControlID="txtStateName"
WatermarkText="State ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtPin" CssClass="textbox"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender14" runat="server" TargetControlID="txtPin" WatermarkText="Pin Code ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<asp:TextBox runat="server" ID="txtComment" TextMode="MultiLine" CssClass="textboxMulti"></asp:TextBox><asp:TextBoxWatermarkExtender
ID="TextBoxWatermarkExtender13" runat="server" TargetControlID="txtComment" WatermarkText="Comments ">
</asp:TextBoxWatermarkExtender>
</td>
</tr>
<tr>
<td>
<br />
<center>
<asp:Button runat="server" ID="btnStore" Text="Save" CssClass="btnConrol" OnClick="btnStore_Click" />
</center>
</td>
</tr>
</table>
<asp:RequiredFieldValidator ID="RequiredFieldValidator6" runat="server" ErrorMessage="Field cannot be left blank"
SetFocusOnError="true" ControlToValidate="txtFullName" CssClass="ErrorMsg"></asp:RequiredFieldValidator><br />
<asp:RequiredFieldValidator ID="RequiredFieldValidator7" runat="server" ErrorMessage="Field cannot be left blank"
SetFocusOnError="true" ControlToValidate="txtEmailId" CssClass="ErrorMsg"></asp:RequiredFieldValidator>
<asp:RegularExpressionValidator ID="regEmail" ControlToValidate="txtEmailId" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"
runat="server" CssClass="ErrorMsg" SetFocusOnError="true" ErrorMessage="Invalid Email" /><br />
<asp:RequiredFieldValidator ID="RequiredFieldValidator8" runat="server" ErrorMessage="Field cannot be left blank"
SetFocusOnError="true" ControlToValidate="txtMobileNum" CssClass="ErrorMsg"></asp:RequiredFieldValidator>
</div>
</div>
</center>
<asp:ImageButton ImageUrl="Images/close1.png" runat="server" ID="btnClose2" Style="float: right;
margin-top: -630px; margin-right: -20px;" />
</asp:Panel>