Follow these steps:
•Flash MIUI China Dev 8.12.13 fastboot rom
•After booting system, flash TWRP 1102 from ADB
•Flash EU beta 8.12.27 on TWRP 1102
• Wipe data
•Flash TWRP 1227 from the TWRP 1102
• Reboot TWRP from the TWRP boot menu
•Then flash MIUI 12 EU beta
•Wipe data
•System reboot
Hope it will help everyone ?
•Flash MIUI China Dev 8.12.13 fastboot rom
•After booting system, flash TWRP 1102 from ADB
•Flash EU beta 8.12.27 on TWRP 1102
• Wipe data
•Flash TWRP 1227 from the TWRP 1102
• Reboot TWRP from the TWRP boot menu
•Then flash MIUI 12 EU beta
•Wipe data
•System reboot
Hope it will help everyone ?