Invalid translation language

I can not publish anything for this error: [30-Sep-2016 16:34:01 Europe/Rome] Uncaught PHP Exception DrupalCoreEntityEntityStorageException: “Invalid translation language (it) specified.” at /home/mysite/public_html/core/lib/Drupal/Core/Entity/Sql/SqlContentEntityStorage.php line 770 How do I fix it? Drupal version:  Drupal 8.x Source: https://www.drupal.org/taxonomy/term/22/feed