Why isn't my native Calendar app syncing in iOS9?

[iMore Question]

native Calendar app not syncing in iOS9.

Upgraded to 6s Plus and native Calendar app did not sync at all. No events show at all even though under the iCloud section it shows my calendars.

 

[Just_Me_D]

Re: native Calendar app not syncing in iOS9.

1. is the device connected to the internet either via Wi-Fi or cellular data?
2. Did you configure the device with iCloud AND have enabled the toggle next to Calendars in the iCloud settings?
3. In the native Calendar app, tap on "Calendars" at the bottom of the screen and then make sure that ALL of your listed calendars have a checkmark in front of them.