When creating a new calendar appointment and notifying users with a push notification - then this user gets notified only that this calendar appointment is shared with him.
This does not mean the user will get a reminder every time the shared calendar appointment is in his calendar.
It is not possible to schedule or automate reminders.
General info: user functionalities depend on the roles & permissions settings. If a certain functionality does not work within your user account, this will be because you don't have sufficient permissions for this.