You are missing an end semicolon on line 9
your variable $logincookie is expecting a string value of “namae” and needs to be enclosed with quotation marks
Below is the corrected code
<!DOCTYPE html>
<html lang="ja">
<head>
<meta charset="UTF-8">
<title>Server console</title>
</head>
<body>
<?php
$logincookie = $_COOKIE;
if ($logincookie == "namae") {
} elseif ($logincookie == null) {
} else {
echo "Sorry, some error prevented access. Please log in again.";
}
echo"<h1>Welcome to the Server console.</h1>";
echo "<a href="."logout.html".">Logout</a>";
echo "<a href="."https://e887b4f9-57f7-4ba1-b25f-5a1633f91c06-00-5n6j13l7d88u.sisko.replit.dev/ad/1/2/3/4/5/6/os-% 20release.php"."> <br> os-
release"
?>
</body>
</html>