Google Adsense with CakePHP?

I'm trying to put an adsense banner in CakePHP and I'm not getting it, the banner just does not show up. How to do this?

footer.ctp

<footer>
<?php echo $this->fetch('script');?>

    <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>

        <ins class="adsbygoogle"
             style="display:block"
             data-ad-client="ca-pub-XXXXXXX"
             data-ad-slot="5082072999"
             data-ad-format="auto"></ins>
        <script>
        (adsbygoogle = window.adsbygoogle || []).push({});
    </script>

</footer>