Appointment created will be in scheduled state. It is not visible in the Open activity associated view by default. Open activity associated view should be showing the appointments which are in scheduled state, because they are still active.
Comments
Thank you for your feedback. This behavior is by design as a distinction exists between activities that are open and those that are scheduled to performed and therefore are not planning to consider this at this point. To view all active activities, a custom view can be created to surface activities that are either open or scheduled.
Category: Unified Experience: Search, navigation and performance