PHP form doesn't send mail – just reloads page - php

Question

I have a problem with my contact form. When I click the send button it just refreshes the page and doesn't send the mail. I tried so many things but couldn't find a solution. I hope somebody can help me.
Here is the php and contact part:
<?php
if (isset($_POST["submit"])) {
$name = $_POST['name'];
$email = $_POST['email'];
$message = $_POST['message'];
$subject = $_POST['subject'];
$body ="From: $name\n E-Mail: $email\n Message:\n $message";
$mail = mail('mymail#gmail.com', $subject, $body);
if ($mail==true)
{
header ("Location: index.php?success=1#contact");
}
else
{
header ("Location: index.php?success=2#contact" );
}
}
?>
....
<form id="contact-form">
<div class="row">
<div class="col-md-6">
<form class="form-horizontal" method="post" role="form" action="index.php">
<div class="form-group">
<label for="name">Name</label>
<input type="text" class="form-control" id="name" name="name" placeholder="Enter name" required="required" />
</div>
<div class="form-group">
<label for="email">
Email Address</label>
<div class="input-group">
<span class="input-group-addon"><span class="glyphicon glyphicon-envelope"></span>
</span>
<input type="email" class="form-control" id="email" name="email" placeholder="Enter email" required="required" />
</div>
</div>
<div class="form-group">
<label for="subject">
Subject</label>
<select id="subject" name="subject" class="form-control" required="required">
<option value="na" selected="">Choose One:</option>
<option value="service">General Question</option>
<option value="suggestions">Suggestions</option>
</select>
</div>
</div>
<div class="col-md-6">
<div class="form-group">
<label for="name">
Message</label>
<textarea id="message" name="message" class="form-control" rows="9" cols="25" required="required" placeholder="CONTACT FORM UNDER CONSTRUCTION! PLEASE USE THE ADRESS AT THE RIGHT/DOWN BELOW."></textarea>
</div>
</div>
<div class="col-md-12">
<input type="submit" name="submit" value="SEND" class="btn btn-skin pull-right" id="btnContactUs">
</div>
</div>
<div class="form-group">
<div class="col-sm-10 col-sm-offset-2">
<?php if($_GET['success'] == 1)
{
echo "Thank you. Your message was sent!";
}
elseif ($_GET['success'] == 2)
{
echo "Sorry, but there were error(s) found with the form you submitted. <br/>Please try again.";
}
?>
</div>
</div>
</form>
</div>
</div>
</body>
</html>

Answer 1

The problem is that you have a form tag inside another form tag.
Try to change the form tag what have the id contact-form to a div tag.