Outlook Exchange Issues on Apple Calendar

My IPhone 7 will not sync correctly with my Exchange email for the last 3 weeks on Apple Calendar. All other calendars like Gmail are working fine with Apple Calendar. As shown in the attached images, it looks like a bunch of duplicate calendars show up sometimes, and most of the time, the Exchange calendar entries just disappear. I have tried deleting the Exchange account and readding, and problem still occurs. Please help as this Exchange account is my work life. Thanks.