I use the Mac Calendar app (OSX Mojave) on my MacBook and IOS calendar app (upgraded recently to iPhone 7, IOS 12) for several shared iCloud calendars, a Google calendar, and an Exchange Calendar (using Outlook for Mac 2016 on my MacBook). They all worked flawlessly until, recently, the Exchange calendar stopped syncing between the Mac Calendar and Outlook/iPhone. Syncing still works perfectly between iPhone and Outlook for Mac for the Exchange calendar. When I add events in either Outlook for Mac or on my phone, they show up in the other one of those two, but not in the Mac Calendar on my MacBook. When I add events to the Exchange calendar on my MacBook, they do not show up either on my phone or in Outlook for Mac. Older events added prior to the problem starting remain visible on all calendars, but if I edit them, the same syncing problems occur. All my other calendars work perfectly between Mac Calendar on my MacBook and the iPhone calendar. I was able to get things to sync once by clearing the library cache on my MacBook, but the problem is still happening and I don't want to have to constantly clear my library cache and re-add the Exchange calendar. I believe this only started around the time I upgraded to iPhone 7, but the problem isn't on the phone - it's on the MacBook. Any help for this problem would be appreciated.