The phone went silent. The amber text disappeared. For a full minute, it was just a black mirror reflecting his tired, scared face.
Using unauthorized service tools or incorrect ROMs can damage the bootloader's security flags. 💡 Verified Solutions 1. Software Force (ADB)
: Ensure you have the correct USB drivers installed. If your PC shows "Waiting for any device," follow a guide like this Fastboot Driver Fix to update your drivers via Device Manager.
If your Oppo has a MediaTek chipset (e.g., Reno 8, A-series), you can bypass Fastboot verification entirely.
Fastboot received an unlock request, but the serial number of your device does not match any authorized serial number on Oppo’s verification server (or embedded key).
Some users on Oppo community forums found that removing the SIM card and then restarting helped bypass certain boot-looping errors.
Here is a comprehensive guide on why this happens and how to resolve it. What Causes This Error?