Type the following command and press Enter:
adb reboot bootloader Your REALME C12 will instantly reboot directly into Fastboot Mode. Some REALME UI versions support this hidden shortcut. It doesn’t always work on every C12 firmware, but it’s worth a try. How to Open Fastboot Mode on REALME C12
Power off your REALME C12 completely. Wait 10 seconds to ensure it’s fully shut down. Type the following command and press Enter: adb