All my Calendar appointments are missing starting with January 2023

lauriefromlansing,

Thanks for letting us know. Next, let's check if your info is showing correctly at iCloud.com: Sign in and use iCloud.com - Apple Support

If everything is showing correctly at iCloud, next check the troubleshooting here: If your iCloud Contacts, Calendars, or Reminders won't sync - Apple Support

If you are using third-party accounts, you can sign in there and see if everything is showing properly, then sign that account in:

Use other contact accounts on iPhone - Apple Support

Set up multiple calendars on iPhone - Apple Support

If the original problem persists after trying the previous steps, please provide us with specifics on what you see for more help, and we will continue from there.

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Cheers!

Hello lauriefromlansing,

We would like to see how we can help you with your missing Calendar events. Which device are you having the issue with? Have you recently changed anything with your email accounts? Make sure the calendar that contains the event has a checkmark by its name. Make sure your calendar account is still set up and turned on for each of your email accounts. Get back to us with some more details, and we can go from there.

Cheers!