Why Don't I Sometimes Get Banner Notifications for Some Applications in A9/A5 2020?

Situation: You don't receive banner notifications for some applications although it is not disabled for the applications.

Applicable to: A9 2020, A5 2020

In order to reduce frequent interruption of banner notifications to users, after a notification banner for an application has been manually slid/closed, the application's banner notifications will be disabled for 1 minute. Therefore, you will not receive the notification banners sent during that period. This is by default and cannot be disabled.