When editing an event it's shown as busy while it's free

[FRvanderVeen]

I sync my work calendar (Microsoft Exchange) to my (Samsung) phone. When I view the event in the Samsung calendar app, it's shown as 'free'. When I view the event in SimpleCalendar it's shown as 'busy'. When I share that event and open the exported ICS file, it contains TRANSP:OPAQUE. So if I understand correctly the database thinks it's a free event.