I was scrolling (rapidly) through the months to get to 2020 to add an entry (which is there no year selector?) and all data disappeared from my calendar - I sincerely hope you have a backup facility somewhere!
In continuation with our previous post on all the exciting updates and improvements that have shaped Zoho Calendar over the past 12 months, Lets delve into more: Bring your calendars together- Introducing Zoho Calendar and Outlook calendar synchronisation