Welcome to iPF!
A few things you could try to get the events to your iPad Air again:
In the Calendar app on your Air, make sure the calendar is enabled/checkmarked, so it is able to sync events to the Air.
In Settings - Mail, Contacts, Calendars, take a look at the account you use for the calendar. "Calendar" has to be enabled.
Remove the email account with the syncing problem and set it up again. Maybe this will solve your issue.
Hope that helps.