The screen will remain black, but the PC will detect a "Qualcomm HS-USB QDLoader 9008" port. This is not standard Fastboot, but it is the best final option for re-flashing firmware using tools like QFIL or MSMDownloadTool (Oppo’s proprietary flasher).
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can be done through two primary methods: using a specific physical button combination or executing a software command via a computer. Primary Method: Physical Button Combination The screen will remain black, but the PC
If your phone is currently powered on and has a working USB connection to a PC, this is the most reliable method. The screen will remain black
Note: Some variants might use instead. If one fails, try the other .