If you experience sync/data issues on Android, but your data is all fine online in your cloud service, you may want to try to reset the Android calendar storage.

THIS WILL DELETE ALL LOCAL CALENDAR DATA ON THE DEVICE! 

Make sure everything is synchronized/backed up before resetting!


To reset, follow these steps:

  1. Go to Android settings - Apps
  2. Enable the option Show system (might be labelled differently depending on the device)
  3.  - Select Calendar Storage (not the Google Calendar app, or system calendar app or aCalendar)
  4. Select Storage
  5. Select Clear Storage (might be labelled differently depending on the device)


Your cloud services should start syncing right away (if data/background settings permit).