ICS feed not working for categories

[filip-van-hoeckel]

[eo_subscribe class="button" title="Voeg toe aan Google Agenda" type="Google" category="schakelonderwijs"]Voeg toe aan Google Agenda[/eo_subscribe] [eo_subscribe class="button" title="Voeg toe aan agenda" type="webcal" category="schakelonderwijs"]Voeg toe aan agenda[/eo_subscribe] [eo_subscribe class="button" title="Voeg toe aan iOS Agenda" type="ical" category="schakelonderwijs"]Voeg toe aan Apple Agenda[/eo_subscribe] Only the webcal version seems to produce data, the others stay blank. It may be worth noting we translated our event permalinks. What could be causing this?