Use latest official TWRP or OrangeFox
To install the ROM, assuming you're on stock MIUI:
- Wipe > format data > type yes ( make sure it's format data and not wipe data )
- Reboot to recovery
- Move ROM zip to internal storage or use OTG
- Flash ROM
- Reboot System
Followed your instructions,
Installed official TWRP , then installed xiaomi.eu 20.5.14 , format data , reboot
All working great, thanks so much for your help, I was stuck on 10.3.15 for a long time and wanted to update to Android 10 MIUI 12
Restoring backup from Google now, so far so good !
Use these links. You need .tgz file decompress it twice, till you have ordinary folders and files (cca 6,5GB). Then use MiFlash 2017 version (in the bottom right corner is option, if you also want to lock your bootloader). Put your phone to fastboot and flash it. It takes about 15 minutes and then you have clean phone.