Outlook for mac isn’t working properly, many functions are greyed including out of office and shared calenders

Ive had my Mac for a year now with office, but i am starting to use it much more as i have recently start a business.

I have serval issues with it including "Out of office" being greyed out, and also "shared calendars" 

Does anyone know how i can repair it without wiping it and starting again? I have so many emails in folders that i can not afford to lose hence why putting it off for so long. 

Thanks