[Plugin: Social] No commenting when using twitter OR facebook

The title says it all, it’s located at https://newsbloggers.ch/

Only the twitter account that is set up as default in the backend can comment. If I try to connect with my twitter account (or facebook), the connection works, but after submitting a comment, the site loads new and there is no new comment at the bottom. Am I doing something wrong?

https://www.ads-software.com/extend/plugins/social/