Update/install TWRP via fastboot. https://xiaomi.eu/community/threads/installing-a-custom-recovery.67841/post-680918
Or use OTG-USB if you want to do it via TWRP
Turn off "always keep Bluetooth on" in the settings.
If you have this setting active, Bluetooth will always turn on automatically the next day. And all your devices will reconnect.
If you are using an official ROM, go to the Xiaomi website.
- xiaomi.eu is a custom ROM created by a group of enthusiasts
- Global EEA ROM (UOPEUXM) is the official firmware from Xiaomi
I will write it clearly and concisely.
Currently it is not possible to unlock CN devices of the 15 series. No way! You're wasting your time trying to figure out a way around this.
Installing with Fastboot:
Download Xiaomi.eu ROM zip file to PC xiaomi.eu_NUWA_OS2.0.107.0.VMBCNXM_15.zip
Extract the ROM zip to a new folder
Power off your device
Boot your device in Fastboot mode (Hold volume down + power buttons)
Connect to PC via USB cable
Run one of the installation...