CRM: WHERE suddenly events and invites GONE from contacts AND leads view

CRM: WHERE suddenly events and invites GONE from contacts AND leads view

We no longer invite leads or contacts as the event section is gone from the layout.
From our end, NO changes have been done.
But now this important section is gone ?! via settings NOTHING can be fixed.

How will this be fixed and why do you change such things without keeping us in the loop?