Q: I Phone syncing with computer

Hi Mj0,

Thanks for using the Apple Support Communities! I'm sorry to hear you are having these issues with your iPhone. I'm a bit unclear on currently how you have your calendars configured, but if you are using iCloud Calendar to sync your calendar data you may find the information and troubleshooting steps outlined in the following article helpful:

Get help using iCloud Calendar - Apple Support

On the other hand, if you are syncing your calendar data directly and using a Windows machine, you may find this article more useful:

If you can't sync contacts and calendars using iTunes for Windows - Apple Support

Regards