PHP snippet shortcode only works once

Hello,

just wondering why my little php snippet only works once.

Added this small script inside a Gutenberg post loop area to add an ACF variable to css.

<?php while (have_posts()) : the_post(); ?>
   <style type="text/css">
   li.post-<?php echo esc_attr( get_the_ID() ); ?> {    
       some css here
   }
   </style> 
<?php endwhile; ?>

Adding the script as a shortcode inside the post loop element works fine on archive template with twenty twenty four.

But if i try to add the script shortcode inside another post loop element on a page, it doesn’t show up and no <style> is added. Seems it code only works once…

I’ve already tried to use it as a universal snippet with an ending ‘?>’
No condition logics.

Can you help? Many thanks in advance!

Best, Sven