After receiving the information notification, why can't the mobile phone slide down from the top of the mobile phone screen to display the notified information?

You can turn off the notification management authority, which can be set according to the following methods, taking Huawei's mobile phone operation as an example:

Step 1: Open Huawei's mobile phone and click Settings on the desktop, as shown in the figure below.

Step 2: After setting, click Apply, as shown in the following figure.

Step 3: After entering the application settings, click Application Management, as shown in the following figure.

Step 4: In the application management interface, search for "Information" and click Enter, as shown in the following figure.

Step 5: After entering the SMS setting interface, click Notification Management, as shown in the figure below.

Step 6, enter the SMS notification management interface, set the notification authority, and turn on the status bar display, banner and screen lock display. After opening, the SMS will be displayed in the notification bar, as shown in the figure below.