Why does my inbox show that a change was made by an Unknown Person?
BusyCal will show "Unknown person" or simply remove the name of the person who made the change because the event was modified / created on a device / app (possibly Apple Calendar) which did not share contact details. Sadly since this is a BusyCal only feature, it only works when you add events from within BusyCal. If in case the event was added in BusyCal, it may not be able to obtain these from your Me Card when:
- BusyCal is denied access to Contacts, OR
- When the event was created by any app other than BusyCal, OR
- When Apple Calendar makes a change and removes the 'modified by' field stored in the event
When it syncs over, BusyCal doesn't know who changed it and so it says 'Unknown Person'. Sadly since this is a BusyCal only feature, it only works when you add events from within BusyCal.
Note that the reason you're seeing these is because you've turned on 'Show me change notifications' for the calendar. To turn these off, double click on the calendar these events belong to, then uncheck the option 'Show change notifications in Inbox'.
unknown, unknown person, modified by unknown