The light in the upper left corner of oppo mobile phone is always on.

1. First, find the "Settings" icon on the phone desktop and click Enter.

2. After entering the setting interface of the mobile phone, drop down the menu, and then select the "notification and status bar" option.

3. Finally, in the notification and status bar interface, turn off the switch in the column "breathing light flashes when receiving the notification".

Note: This answer is applicable to all models of OPPO.