CROM Service
Unlike other regions, Every Samsung device sold in China, the bootloader locked when shipped. This conforms to the Chinese government’s security laws and policies. However , Since enthusiasts are interested in running custom ROM
Therefore, the brand has a very simple solution. All you have to do is install the CROM Service app on your device and unlock it.
If you have bought your phone from China, use the instructions ahead to download CROM Service app and utilize it to unlock its bootloader.