If your iCloud calendar or contact data isn’t syncing between your devices, an important troubleshooting step is to figure out where the bottleneck is. What I usually do is add a test contact (for example) to my Mac and one to my iPhone, and then I log on to iCloud.com with my Apple ID to see which contact arrives. Whichever one doesn’t appear identifies the device that’s the culprit!
In my experience, though, the problem is almost always with iOS, and if that seems to be the case for you, there’s a quick trick you can try to get things running smoothly again. It’s a way to force your calendars or contacts to refresh themselves, and it’s so quick! You don’t even have to restart any devices, and whoo-hoo to that!
So to refresh your iCloud calendars, here’s what you’ll do. 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! After the gear stops spinning, go out and check to see if the events you’re expecting have shown up.
The process is very similar for the Contacts app. Open that, and then tap “Groups” at the top-left. If you don’t see the “Groups” button, you might need to first select “All Contacts” in the upper-left to go back out to the main list view.
Once you’re looking at your groups, do the same thing that you did in the Calendar app—drag down on the list until you see the spinning icon.
Then go search for your previously unsynced contacts.
You shouldn’t have to take these steps very often (and if you do, it could indicate that the issue needs further troubleshooting), but if you’re having problems with syncing every now and again, this could be just the ticket!