Release the buttons once the OPPO logo appears. Wait for the language selection screen. Select Language : Use the touch screen or volume keys to select Install Firmware Install from storage device From SD card Find and tap on the firmware file you downloaded.
Flashing an Oppo A57 using an SD card (often called a "Force Upgrade" or "Local Update") is a reliable method to unbrick a device, fix bootloops, or downgrade the operating system without needing a PC. flash oppo a57 via sd card work