Great. But there is a bug when run BCA Mobile application. Pop up message "Please insert sim card" appeared and the app force closed. It did not happen when i use MIUI 12 china rom. Thanks.
Sure there is. Please download the tools that you need for flashing the phone. Install the qualcomm driver to your computer. Please googling to search the driver. And adb tools for android. And then mi flashing tool. And off course the rom. Run fastboot mode on the phone. Run cmd in adb folder...
In my experience first of all flash the phone with dev rom and then log in with your mi account. Maybe it is necessary to complete your profiles in your mi account. And then do the unlock procedure to unlock the bootloader. Hope this help your problem.
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