When I create a new event in Kontact/Korganizer, add attendees, and then click "Schedule..." none of the meeting participants' free/busy information or other meetings show up.

Hi!

When I create a new event in Kontact/Korganizer, add attendees, and then click “Schedule…” none of the meeting participants’ free/busy information or other meetings show up.
Instead, the “Scheduling” window that opens shows the list of attendees and an otherwise empty timeline under the “visual search” tab and the “automatic search” tab is all blank, too.
If I add myself as attendee at least for myself the scheduling will show some availabilities, though, the scheduling dialogue still seems somewhat buggy/misbehaving as the shown timeline for finding meeting times does not update as I change the earliest/latest time to start fields.

Does scheduling in Kontact/Korganizer work for anyone?

ldap is set up correctly and I can search contacts, but I am not sure where to even start debugging this – what is usually providing the information for scheduling?
(Things work in thunderbird with the same caldav calendar and ldap setup.)

Kontact Version 5.20.1 (22.04.1)
KDE Frameworks Version 5.94.0
Manjaro stable

Thanks!