Oppo has tightened bootloader unlocking in certain regions (especially for devices sold in Mainland China vs. Global).
If your PC sees the device as a "Marshall London Bootloader" or a generic "Android Device," the serial verification will fail.
Oppo (and Realme) devices use a strict verification process for bootloader unlocking. The "Serial Not Match" error typically triggers for three reasons: the serial is not match fastboot unlock verify fail oppo
Unlocking the bootloader will and potentially void your warranty. Always back up your data before attempting these steps.
Ensure the APK version matches your Android version (e.g., don't use an Android 11 unlock tool on Android 13). Check forums like XDA Developers for the specific version for your exact model number (e.g., CPH2023). 2. The "Wait and Sync" Method Oppo has tightened bootloader unlocking in certain regions
If you have tried all the above and the error persists, it is likely that Oppo has patched the exploit for your specific firmware version. In this case, you may need to wait for a newer version of the Deep Testing tool or a community-made exploit.
Many users see "Review Successful" in the app and immediately jump into Fastboot. However, it can take time for the device's internal flag to sync with the server’s approval. Oppo (and Realme) devices use a strict verification
Do you have the and Android version of your Oppo phone so I can look for a specific tool version?
If you are using a Chinese ROM, the global Deep Testing APK will almost always return a "Serial Not Match" error. You must use the Chinese version of the app linked to an OPPO ID registered in that region. Important Reminder
Fixing the "Serial Is Not Match Fastboot Unlock Verify Fail" Error on Oppo