with the Apple iOS bug that was fixed just this Spring (2011) with iOS 4.3, prior to that bug fix, a Decline by. Exchange Outlook Calendaring Problems (lost meetings, delegate problems, etc).From this point forward, iPhone OS was renamed iOS. iPhone13C2 = iPhone 12 Mini (?) iPhone13C3 = iPhone 12 Pro iPhone13C5 = iPhone 12 Pro Max. iOS devices unfortunately do not register with ActiveSync or other tools with a logical clear human readable version number.Just change the “Mail Days to Sync” field to “No Limit”.
Reset Network settings via Settings -> General -> Reset -> Reset Network Settings. Go back all your mail accounts and reset password.