New Outlook for MAC

My MAC updated to the New Outlook last night. Unfortunately the Calendar had no calendar events in it. So I reverted back to the old outlook and the calendar events were also missing here. My contacts were also missing. I received notification reminder for a calendar event today but the calendar event itself is not showing. I had a personal Calendar and a Work calendar but neither are listed as previously.

I just want to see the calendar events that I had previously inputted and could previously see!