I have done all the steps and it works perfectly. I leave a small tutorial for people who do not fully understand how to do it, so you can do it without fear.
My device is a Xiaomi 12, but it should work with any other phone that has MIUI 14 ROM from xiaomi.eu.
IMPORTANT: This method is only valid for the Stable ROM.
First step: Back up the data on the device and transfer it to a computer. (Not mandatory, but recommended).
Settings → My device → Backup and restore → Mobile device → (Select what you are interested in) Back it up.
It will take a long time depending on what you have in storage, if you see that the number does not change or has stopped suddenly, do not worry, the copy continues to work unless the device freezes. As soon as it is, transfer it to the computer. You will find the copy in the folder MIUI → backup → AllBackup → daymonthyear_hourminuteseconds (it is a folder with numbers in the name, you have to move the whole folder, without compressing it or anything).
Second step: Install TWRP (if not already installed)
https://xiaomi.eu/community/threads/howto-install-recovery-image.66211/ (main tutorial)
https://xiaomi.eu/community/threads...all-twrp-and-xiaomi-eu-roms-on-poco-f3.61624/ (extra info.)
Third step: Install the latest ROM available if it is not already available. You can download it from here or directly on the device from the update section.
Fourth step: Install the .apk file that appears in the banner that pops up when you open the Update section.
Fifth step: Delete ALL data from the Google Play application (yes, the app store) and reboot the device.
Sixth step: That's it. Everything should work perfectly.
(if anyone sees an error, please correct me)
(if something is badly written or translated, forgive me, my phone is in Spanish)