滚动时，我的网站上有ajax加载帖子。问题在于出现了重复的帖子。我不明白为什么会这样。只有一些帖子有重复。这是我的密码function.php:

function loadmore_get_posts(){
  $paged = !empty($_POST[\'paged\']) ? $_POST[\'paged\'] : 1;
  $paged++;

  $args = array(
    \'paged\' => $paged,
    \'posts_per_page\' => $_POST[\'posts_per_page\'],
    \'post_type\'      => \'post\',
    \'post_status\' => \'publish\',
    \'cat\' => $_POST[\'cats\']
    );

  query_posts($args);
 
  while( have_posts() ) : the_post();
    get_template_part( \'this is template\' );    
  endwhile;
  die;
}
add_action(\'wp_ajax_loadmore\', \'loadmore_get_posts\');
add_action(\'wp_ajax_nopriv_loadmore\', \'loadmore_get_posts\');

这是普通javascript中的ajax：

let ajaxurl = \'<?php echo admin_url(\'admin-ajax.php\') ?>\';
let section_posts = 1;
let postData = new FormData();

postData.append(\'action\', \'loadmore\');
postData.append(\'paged\', section_posts);
postData.append(\'posts_per_page\', 9);
postData.append(\'cats\',  <?php print json_encode(get_selected_cats())?>);

  const xhr = new XMLHttpRequest();
  xhr.open(\'POST\', ajaxurl);

  xhr.addEventListener(\'readystatechange\', function (data) {
  if (this.readyState === 4 && this.status === 200) {
     section_posts++;
     document.querySelector(\'.articlefeed_template\').innerHTML += data.target.responseText;
  } else {}
     xhr.send(postData);
  }

请告诉我我做错了什么？谢谢