Why did Huawei's SMS notification bar disappear in an instant on the mobile phone screen and how did it stay for a long time?

1. Click the "Settings" App on the desktop to enter the "Settings" function list. 2. In the "Settings" function list, click "Apply". 3. In the "Application" function list, click "Application Management". 4. In the application management function window, in the application list, click Info. 5. In the "Application Information" function window, click "Notification Management". 6. In the "Notification Management" function window, click the function button on the right side of the "Allow Notification" tab to open the function and complete the operation.