php cookide pleskde çalışmıyor

<?php
session_start();
 
if(!isset($_COOKIE["cozunurluk2"])) { 
$_SESSION[iterate]=1; 
?> 
<script language="javascript"> 
writeCookie(); 
 
function writeCookie() 
{ 
 
var the_cookie = "cozunurluk2="+ screen.width; 
 
document.cookie=the_cookie 
 
location ='<?php echo $_SERVER['PHP_SELF'];?>'; 
} 
</script> 
<?php 
} 
else{
$cozunurluk = $_COOKIE["cozunurluk2"]; 
} echo $cozunurluk; ?>