通过AJAX发布时，注释会显示两次，但在页面重新加载时只显示一次

I used the following codes to add comment to a post and display it without refreshing the page, but somehow, it displays the comment twice instead of once, but it only saves it once in the database. When I refresh the page, it displays each comment only once though, so i guess the problem is with the "ajax response". Here are the codes, thanks for any help.I used the following codes to add comment to a