我正在使用自定义分类法创建自定义帖子类型，同时为自定义帖子提交前端表单。它正在创建帖子，但并没有创建我已经设置的新分类法，只需要添加自定义分类法

<form action=\'\' method="post" id="drop_message">
  <div class="input-group">
    <div class="first">
        <label for="first-name-opt">First Name:</label>
        <input type="text" name="name" id="name" placeholder="John Doe" class="tag-msg">
    </div>
    <div class="middle">
        <label for="email">Email:</label>
        <input type="email" name="email" id="email" placeholder="[email protected]" class="tag-msg">
    </div>
    <div class="last">
        <label for="birthdate">Date Of Birth:</label>
        <input type="text" name="birthdate" id="birthdate" placeholder="DD - MM - YYYY" class="tag-msg">
    </div>
      <div class="submit">
         <input type="submit" name="submit" id="submit" value="Leave a Message">
      </div>
    </div>
</form>

<?php 

if( \'POST\' == $_SERVER[\'REQUEST_METHOD\']) {

    $name = $_POST[\'name\'];
    $email = $_POST[\'email\'];
    $birthdate = $_POST[\'birthdate\'];


    $post = array(
            \'post_title\'    => $title,
            \'post_content\'  => $description,
            \'post_author\'   => $user,
            \'post_status\'   => \'publish\',
            \'post_type\' => \'messages\',
             \'tax_input\'     => array( 
                $name,
                $email,
                $birthdate,
            ),
        );

    $pid = wp_insert_post( $post );
    wp_set_object_terms( $pid, $name, \'name\');
    wp_set_object_terms( $pid, $email, \'email\');
    wp_set_object_terms( $pid, $birthdate, \'dob\');
}