Thanks for making it clear that you did not even try to understand the issue, even if it was explained dozens of times on the forum ...
The camera require a piece of software from Xiaomi to work. This software come from the official Global ROM, and is now completely outdated compared to the latest ROMs Xiaomi.eu released, be it on the MIUI version, or Android version.
There is nothing to fix directly, as "disappointed" as you are
Wait until the official MIUI13 ROM is released, maybe it will help providing a solution