Javascript 表格'；s提交按钮不工作。你能告诉我我想要什么吗；我做错了？ 提交

这是我的剧本：-----------------------------------------

<form id="contactForm" name="enquiryform" method="POST" action="enquirymail.php" class="contact-form">
    <div class="col-md-6 col-sm-6 col-xs-12">
        <input type="text" id="name" class="form-control" placeholder="Name" required data-error="Please enter your name">
        <div class="help-block with-errors"></div>
    </div>
    <div class="col-md-6 col-sm-6 col-xs-12">
        <input type="email" class="email form-control" id="email" placeholder="Email" required data-error="Please enter your email">
        <div class="help-block with-errors"></div>
    </div>
    <div class="col-md-12 col-sm-12 col-xs-12">
        <input type="text" id="msg_subject" class="form-control" placeholder="Subject" required data-error="Please enter your message subject">
        <div class="help-block with-errors"></div>
    </div>
    <div class="col-md-12 col-sm-12 col-xs-12">
        <textarea id="message" rows="7" placeholder="Massage" class="form-control" required data-error="Write your message"></textarea>
        <div class="help-block with-errors"></div>
    </div>
    <div class="col-md-12 col-sm-12 col-xs-12 text-center">
        <button type="submit" id="submit" class="contact-btn">Submit</button>
        <div id="msgSubmit" class="h3 text-center hidden"></div>
        <div class="clearfix"></div>
    </div>
</form>