Dear Scott and Enrico,
Thank you for feedback on the Social Connect.
The issue happens because the permission "user_interest" is no more available from Facebook. Facebook has already removed it but it is still there in the product's source code. So to fix the problem, the permission "user_interest" should be removed out of the source code.
If you need any assistance removing it, please feel free to create a ticket in Client Area. Our support team will get in touched and guide you through.
Best Regards,
YouNet