[Evolution] Certain appointments don't show up on CalDav calendar

[no_interest fastmail fm]

Dear all,

I run Evolution on my laptop and on my desktop. Same version (3.22.6) on
same Distro (Fedora 25). The laptop now has the annoying problem that
the CalDav calendar (through Fastmail) doesn't show all appointments in
the calendar. The Desktop has no problem whatsoever. The problem
surfaced suddenly, both systems are up to date. Could I get some help on
how to best debug this strange problem? (I have not been able to see a
specific issue with the dates that do not show up, so my first idea is a
problem on the laptop's system).

Kind regards,

Matthijs