validation errors in asp.net

<table align="center" cellpadding="4" cellspacing="4">
                    <tr>
                        <td align="right">
                            Code
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtBrCode" runat="server"
                                ontextchanged="TxtBrCode_TextChanged" AutoPostBack="true"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtBrCode"/>
                        </td>
                        <td align="right">
                            Name
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtBrName" runat="server"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtBrName"/>
                        </td>
                    </tr>
                    <tr>
                        <td align="right">
                            Region
                        </td>
                        <td align="left">
                            <asp:DropDownList ID="DdlRegion" runat="server">
                            </asp:DropDownList>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="DdlRegion"/>
                        </td>
                        <td align="right">
                            Phone
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtPhone" runat="server"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtPhone"/>
                            <asp:RegularExpressionValidator ID="RegularExpressionValidator3" runat="server" ErrorMessage="Invalid Phone Number"
                                Text="*" ControlToValidate="TxtPhone" ValidationExpression="\d{10}"/>
                        </td>
                    </tr>
                    <tr>
                        <td align="right">
                            Mobile
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtMobile" runat="server"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator5" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtMobile"/>
                            <asp:RegularExpressionValidator ID="RegularExpressionValidator1" runat="server" ErrorMessage="Invalid Mobile Number"
                                Text="*" ControlToValidate="TxtMobile" ValidationExpression="\d{10}"/>
                        </td>
                        <td align="right">
                            Email
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtEmail" runat="server"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator6" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtEmail"/>
                            <asp:RegularExpressionValidator ID="RegularExpressionValidator2" runat="server" ErrorMessage="Invalid Email ID" Text="*"
                             ControlToValidate="TxtEmail" ValidationExpression="\w+([-+.']\w+)*@\w+([-.]\w+)*\.\w+([-.]\w+)*"/>
                        </td>
                    </tr>
                    <tr>
                        <td align="right">
                            ContactPerson
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtContactPerson" runat="server"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator7" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtContactPerson"/>
                        </td>
                        <td align="right">
                            Address
                        </td>
                        <td align="left">
                            <asp:TextBox ID="TxtAddress" runat="server"></asp:TextBox>
                            <asp:RequiredFieldValidator ID="RequiredFieldValidator8" runat="server" ErrorMessage="Required"
                                Text="*" ControlToValidate="TxtAddress"/>
                        </td>
                    </tr>
                    <tr>
                        <td colspan="4" align="center">
                            <asp:Button ID="BtnSave" runat="server" Text="Save" OnClick="BtnSave_Click" />
                            <asp:Button ID="BtnCancel" runat="server" Text="Cancel" OnClick="BtnCancel_Click" />
                        </td>
                    </tr>
                    <tr>
                        <td colspan="4" align="center">
                            <asp:ValidationSummary ID="VS" runat="server" CssClass="ValidationSummaryclass" ShowSummary="true" EnableClientScript="true"/>
                        </td>
                    </tr>
                </table>

protected void BtnCancel_Click(object sender, EventArgs e)
        {
           Response.Redirect("Branches.aspx");
        }