Isotope filter not working - please help

Isotope filter not working - please help

Hi

I would like to filter the posts on my wordpress based page by using jquery.isotope.min.js

I see that script is loaded correctely (via footer.php).

Code looks as following:

<div id="filters_sidebar" class="well">
<a class="filter_sidebar filter_header" data-filter="*" href="#">RECENT</a>
<li> <a id="acties" class="filter_header-sub filter-data" data-filter=".acties" href="#"> Acties </a>
</li>

acties is an existing category slug

however when i click this link nothing happens

hope that someone can point me in the right direction to get this resolved...

thank you so much

Jeroen