Why am I unable to create appointments on my iPad's calendar?

[iMore Question]

For some unknown reason I am no longer to make appointments on my iPad calendar.

 

[Just_Me_D]

Do any or all of the following:

1. reboot your device and then try to create a calendar event.
2. If the calendar is associated with an email service, sign out of the email service in the Mail, Contacts, Calendars setting and then re-configure the account on the device.
3. If you're using a 3rd-party calendar app, delete it and then re-install it.