How can I check if the UID already exists? I had a manual entry for the event and later on tried to import the “official” .ics file - and failed.
In a second attempt to import the .ics file with Jolla’s Pfefferberg event, I first deleted my manual entry but couldn’t import the .ics file either.
I noticed that updating existing calendar events via a newer .ics file never works. I always have to delete the old event first before newly importing the updated event. That may correlate with the UID thing you are addressing.
But this doesn’t fit the instant case.