​提交后提示没有找到页面

<section class="question">
      <!--form表单-->
      <div class="audition">
        <form id="mfst" action="{$post_url}&is_show_msg=1"  method="post" name="myform">
          <h2 class="tc">预约免费试听</h2>
          <p>
            <input type="text" name="data[name]" id="name" class="intxt" lay-verify="required" placeholder="请输入学生姓名" /></p>
          <div class="selete">
            <div class="filter-box filter-box1">
              <div class="filter-text">
                <input class="filter-title" type="text" readonly placeholder="小学" />
                <i class="icon icon-filter-arrow"></i>
              </div>
              <select name="data[nianji]">
                <option value="小学" selected>小学</option>
                <option value="初中">初中</option>
                <option value="高中">高中</option></select>
            </div>
            <div class="filter-box filter-box2">
              <div class="filter-text">
                <input class="filter-title" type="text" readonly placeholder="语文" />
                <i class="icon icon-filter-arrow"></i>
              </div>
              <select name="data[kemu]">
                <option value="语文" selected>语文</option>
                <option value="数学">数学</option>
                <option value="英语">英语</option>
                <option value="物理">物理</option>
                <option value="化学">化学</option>
                <option value="政治">政治</option>
                <option value="历史">历史</option></select>
            </div>
          </div>
          </table>
          <p>
            <input type="text" name="data[phone]" id="tel" class="intxt" placeholder="请输入您的手机号码"></p>
<input type="submit" onclick="dr_ajax_submit('{$post_url}', 'myform', '2000', '{$rt_url}')" class="appointment" name="submit" value="立即预约">
          </form>
      </div>
    </section>

提交后提示这个，辛苦看看