Uhh, I have some ideas, but it's late for me now, I'll try to help tomorrow. ~All I can do now is share a guide I've compiled, here. (Btw, the latest beta from xiomi.eu seems buggy, the previous week's one is probably better.)HELP!
I have ventured to flash my Mi 10...unfortunately not successful. I hope someone of you can help me...
I have installed TWRP completely according to your instructions. The first strange thing was that a lock and a "Swipe to unlock" slider appeared at the bottom. The touch did not work either. I then connected a mouse and it worked.
Then I wanted to do the wipe, but then "Unable to mount /data/media/TWRP/.twrps" popped up and "Unable to mount storage". The internal storage is also shown as 0MB. I tried the video mentioned below and the steps in it (from Ext4 to Ext2 and back again). Didn't bring anything unfortunately.
A system (MIUI) unfortunately also seems to be no longer installed, anyway I can only boot into TWRP and it says that no other system is available.
What can I do? You guys would be my last resort!
Many greetings and thanks in advance