textbox is not editable after a click

textbox is not editable after a click

i have problem textbox is not editable after a single click. I have to
make double to click to write in it. On single click it cursor goes to
upper text box. How to remove it. please help me. Thanks in advance
code is here
<form id="form1" class="form-style" method="post" runat="server">
<label> Area(in Sq Ft)
<asp:RequiredFieldValidator ID="RequiredFieldValidator1"
runat="server" ControlToValidate="Txtarea" ValidationGroup="1">
<img alt="" src='<%=ResolveClientUrl("~/Images/erroricon.png")%>' />
<asp:TextBox ID="Txtarea" runat="server">
Region
<asp:TextBox ID="Txtregion" runat="server">
Name
<asp:RequiredFieldValidator ID="RequiredFieldValidator2"
runat="server" ControlToValidate="TxtName" ErrorMessage="Enter Your
Name" ValidationGroup="1"> <img
alt="" src='<%=ResolveClientUrl("~/Images/erroricon.png")%>' />
<asp:TextBox ID="TxtName" runat="server">
Mobile No.
<asp:TextBox ID="txtmobile" runat="server">
<asp:RegularExpressionValidator ID="RegularExpressionValidator1"
runat="server" ValidationExpression="^[0-9]{10}"
ControlToValidate="txtmobile" ErrorMessage="Incorrect Number"
ValidationGroup="1">
<img alt="" src='<%=ResolveClientUrl("~/Images/erroricon.png")%>' />
<asp:Button ID="Btnsave" runat="server" Text="Send" Width="78px"
Style="color: #fff;
font-size: 12px; line-height: 15px; background:
url(../images/button-1.jpg) 0 0 repeat-x #08489f;border-top: #339ed3
1px solid; border-right: #2881c3 1px solid; border-bottom: #1a62b1 1px
solid;border-left: #2881c3 1px solid; display: inline-block;
text-decoration: none;padding: 5px 21px 7px 19px; cursor: pointer;"
OnClick="Btnsave_Click" ValidationGroup="1" />
<asp:Label ID="Label1" runat="server" ForeColor="Black">
</label>
</form>