PHP：在div中填充数据

Question

我试图在div中填充数据。哪个工作正常，但是，第一个div数据将重复一次，如附图所示。我无法在代码中看到任何逻辑错误，希望有人能帮助我。

<div class="posts">
<?php
        include("dbconn.php");
        $sql = "SELECT *
                FROM posts p
                INNER JOIN users u
                ON p.userID=u.userID
                INNER JOIN courses c
                ON p.courseID=c.courseID;"; 
        $result = mysqli_query($conn, $sql);

        if (mysqli_num_rows($result) > 0) {
            while($row = mysqli_fetch_assoc($result)) {
?>
                  <section class="post">
                    <header class="post-header"> <img class="post-avatar" height="48" width="48" src="image/common/tilo-avatar.png">
                        <h2 class="post-title"><?php echo $row["postTitle"]; ?></h2>
                        <p class="post-meta"> By <a href="#" class="post-author"><?php echo $row["nickname"]; ?></a> under <a class="post-category post-category-design" href="#"><?php echo $row["courseName"]; ?></a> </p>
                      </header>
                    <div class="post-description">
                        <p> <?php echo $row["postContent"]; ?> </p>
                    </div>
                </section>
<?php
            }
        } else {
            echo "no questions yet";
        }
?>
</div>

image