You can drop down the status bar to see if the tile has the function of "auto-rotating screen" enabled and turned it off, or in the software settings, the screen display is set to follow the system.

The following are the specific steps:

1. Open the settings of the mobile phone, and click Display and Brightness.

2. Click the switch behind the vertical screen lock.

When the switch turns into color, it turns on. When turned on, the landscape mode is forcibly turned off.