Calendar sync not wokring

Calendar events aren't syncing to with my Bangle.js 2 (it used to work a while back, but I didn't need them back then).

The GadgetBridge log looks promising:

15:08:10.741 [main] INFO  n.f.g.e.CalendarReceiver - event id=418 is yet unknown to device id=1

and then one of the following lines per calendar event to be synced:

15:08:10.784 [main] DEBUG n.f.g.s.DeviceCommunicationService - Service startcommand: nodomain.freeyourgadget.gadgetbridge.devices.action.add_calendarevent

But nothing appears on the Bangle.js - the android.calendar.json remains empty.

I've looked at the "device Debug log" (with "Debug" set to BOTH on the watch), but all I found related to calendar syncs was:

{"t":"force_calendar_sync","ids":[]}

I've also tried to completely remove the device from Gadgetbridge and re-connect.

What else can I do to help with troubleshooting?