Thanks for the help.
I have:
New error:
ERROR: This package required firmware from an Android 10 based MIUI build. Please upgrade firmware and retry!
And I’m on Android 11 in fact.
Also, I have a red line at the top of the screen:
E: Unable to decrypt FBE device
So what can I do? Reinstall the native OS and do not upgrade Android to stay on its 10th version (I don’t know how to do this) 
> UPDATE: I can’t even answer in public or PM because I’m a newbie on this forum. If a moderator can unblock me… The concern for me, aside from not being able to free my phone, is that I need it by tonight. Currently, I’m at someone’s house to have their Internet connection but as of tomorrow morning, I’m going back home with no connection except via the phone, and it’s not working anymore.
**> **
> So I’m thinking of trying to reinstall the default system, see if the Android version is 10 or 11 and, if the former, try again or, if the latter, wait for it to settle down and release it later.
**> **
> By the way, how do I reinstall the default OS version?
Xiaomi phones do not require a tool to unlock, it happens directly from the OS itself.
I downloaded the latest available package miui_RAPHAELEEAGlobal_V12.5.1.0.RFKEUXM_dd92b7128a_11.0.zip for my phone version and imported it via TWRP. The installation went well. MIUI launches, asks me to restore the device, and then Google goes to work. And when I get to the last screen, I do Done, the screen turns white and then comes back to this last screen, I’m stuck in a kind of loop and I don’t know how to get out of it.
And no, it’s not the fact of answering to other subjects, it’s really a limitation of the CMS managing the forum, the error message is quite explicit.

VoilĂ .