Oppo’s stock recovery is case-sensitive and picky.
Visit the official Oppo support forum or use SP Flash Tool (for PC) if the SD card method fails repeatedly. Good luck! flash oppo a57 via sd card work
📌 This method does wipe data and cannot fix a bricked device – it’s only for system updates. For a full flash to reset or unbrick, you need TWRP. Oppo’s stock recovery is case-sensitive and picky