calendar won't sync to events older than a month

Hi,

I have iPhone5s running iOS9.3.1. My calendar is not showing any past events older than a month. Currently, all the events older than 2 April 2016 is not showing up on my phone. I can see the old events on the iCloud Calendar website.

If I create an event on 1 April 2016 on my iPhone, it will disappear after 2 seconds, but it will appear on the iCloud calendar website. If I create any events after 2 April 2016, it works fine.

Is there any settings to control how far you can sync in the calendar app?

I have tried the followings and nothing fixed this problem:

1. Turn off the iCloud calendar in the Settings and turn back on again.
2. Resetting the phone by holding home and power key for few seconds.
3. Clos the calendar app and reopen the app.

Has anyone got any idea?

Thanks.