Can't display adsense adds

I have started a wordpress blog for 99 dollar a year.
Now I am trying to put adsense adds on my website, but not matter what, it doesn’t work.

This is my blog: http://earthreview.net/

I only see a square box and underneath it says: (adsbygoogle = window.adsbygoogle || []).push({});

can anyone help please?

This is my original code:

<script async src=”//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js”></script>
<!– Sidebar 2 –>
<ins class=”adsbygoogle”
style=”display:inline-block;width:300px;height:250px”
data-ad-client=”ca-pub-7508935516671459″
data-ad-slot=”2099399769″></ins>
<script>
(adsbygoogle = window.adsbygoogle || []).push({});
</script>