导航栏出现两次不尊重php if语句

I am trying to change my navigation bar depending on whether the user has signed in. Eventually also checking whether the user is an admin or not and having different list items depending on these conditions.

The issue is since my condition is in PHP it doesn't seem to respect the if statement and when the page is loaded both ul are shown.

I have a session start at the top of my page so the value of "loggedin" should be stored.

<header>
<div class="container">
    <div class="Logo">
        <img src="./images/LogoSmall.png" width="60px" height="60px" alt="Logo">
        <h2> Quality Speakers Global </h2>
    </div>
    <div>
    <nav>
    <?php
        if($_SESSION["loggedin"] == "yes"){
        ?>
        <ul>
            <li class="current"><a href="Index.html">Home</a></li>
            <li><a href="Register.html">Login/Register</a></li>
            <li><a href="Slideshow.html">Products</a></li>
            <li><a href="Report.html">Report</a></li>
            <li><a href="userpage.php">My Account</a></li>
        </ul>
    <?php } else{?>
        <ul>
            <li class="current"><a href="Index.html">Home</a></li>
            <li><a href="Register.html">Login/Register</a></li>
            <li><a href="Slideshow.html">Products</a></li>
            <li><a href="Report.html">Report</a></li>
        </ul>       
    <?php       
    }
    ?>

    </nav>
</div>
</header>

What i want is to only show the ul depending on the condition

here is my php login code:

<?php

  session_start();

  $con = mysqli_connect('localhost','root','pass1','accounts');

  if(isset($_POST["UsernameLogin"])) {

      $Logusername = $_POST['UsernameLogin']; 
  }

  if(isset($_POST["PasswordLogin"])) {

      $Logpassword = $_POST['PasswordLogin'];
  }

  $query = " select * from users where username = '$Logusername' && password = '$Logpassword'";

  $result = mysqli_query($con, $query);

  $row = mysqli_fetch_assoc($result);

  $num = mysqli_num_rows($result);

  if($num == 1) {
      $_SESSION["username"] = $Logusername;
      $_SESSION["level"] = $row["usertype"];
      $_SESSION["loggedin"] = 'yes';

      if($_SESSION["level"] == "admin") {

          header('location:AccountsPage.php');
      } else {

          header('location:userpage.php');
      }   
  } else {
    header("Location: Index.html");

  }

?>

Your index.html page is not being parsed as php. Change the extension to .php or change configuration to also parse html files.