Summary
To force iCloud Contacts & Calendars to sync, open the Calendar app on your iOS device and touch the “Calendars” button at the bottom. Then, drag down on the list and release to make a small icon appear at the top which’ll spin for a moment or two.
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If these steps don't resolve the issue, contact Apple Support for assistance.
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According to
Summary
Open the Calendar app on your iOS device, and then touch the “Calendars” button at the bottom.
When you get to your calendars, drag down on the list and release. You should see a small icon appear at the top which’ll spin for a moment or two (if it disappears immediately, be sure you’re dragging down far enough).
That’s it!
iOS: Forcing iCloud Contacts & Calendars to Sync – The Mac Observer
macobserver.com
Summary
If your iCloud Contacts, Calendars, or Reminders aren't appearing on all the devices that you use with iCloud, Apple Support provides steps to check the system status, refresh the contacts and calendars, check app settings, and set iCloud Contacts, Calendars, or Reminders as the default account. If these steps don't resolve the issue, Apple Support recommends contacting Apple Support for assistance.
If your iCloud Contacts, Calendars, or Reminders won’t sync - Apple Support
apple.com
In Calendar on your Mac, update calendars automatically or manually. macOS Ventura 13 macOS Monterey 12 macOS Big Sur 11.0 macOS Catalina 10.15 macOS Mojave ...
Refresh calendars on Mac - Apple Support
apple.com
