Change default calendar

For some reason the default calendar on my wife's iPad is entitled 'Work'. It doesn't sync with iCloud but the other calendars do. There doesn't seem to be an option to delete the Work calendar or change the default. This means that every time she enters something on the calendar she has to change from Work to her calendar.

Settings - Mail,contacts,calendars

Scroll down to the Calendar section. Here you can change the default calendar

Many thanks.

If you log into iCloud.com on your iMac can you see the contact in there?

Are all your devices using the same icloud login details?