CaviaPorcellus

Just wanted to add that it's definitely not just a CM13 thing: I just got this error on a Nexus 5 using stock Android 6.0.1 (MMB29V). Also, there were no...

I also have this issue. I wonder if it's an issue with DAVdroid in some way. When I used CalDAV-Sync with Calendar Notification I would never get duplicates.