Why doesn't Xiaomi mobile phone display the notice in the notice bar?

It is possible that the lock screen is not displayed, so there will be no notice when the screen is locked. You can't see the notification until you unlock your phone.

Setting method:

First, open the settings-notification bar and status bar. As shown below.

Two, open it. Select "Drop Down When Screen Locks". Then when the screen is locked, you can also drop down to view the notification information.