Hello Marco Ficelle,
Sorry for late reply to this,
I have checked in your site, it seems like you already removed this apps User — Article from your application and your Joomla article is not store in the stream from EasySocial, then it doesn't work,
Based on this requirement, you should have install the EasySocial - content plugin and installed User -- Article apps in your site first.
Then create a new Joomla article, so it will create a stream ID for this Joomla article, only can trigger this comment.
Make sure that you have installed this apps User — Article, then created a new Joomla article in your site and test the like/comment and see how it goes. Please advise.