@josele13 Indeed, ADB does not recognize the telephone: sudo adb devices does not give anything.
How to cure it ?

@magic
hello, did you manage to get your phone back? Otherwise I can give you the procedure under windows 10.

@josele13 hi, i managed to unbrick my redmi note 7 via test point mode, which requires rear window removal and MiFlash in authorized mode. that is done !
Now, I installed android 9 but after 2 attempts to install ubport, it still hangs on Waiting for device Adb is scanning for device.
However, the smartphone is in developer mode, OEM unlocked, USB debugging enabled and allowing USB downloads. I checked the unlock with miflash_unlock.
The PC is under ubuntu 20.04.
Does somebody have an idea ?

@jmla I think the installation of ubport could be good if i can install ADB 1.0.41on ubuntu 20.04. But i don't find link for it.

@stanwood Thanks, but how do you reflash android 9 now that everything seems stuck?

@whitemagik Bonjour, j'ai aussi tenté d'installer UBports sur un xiaomi redmi note 7. Il était sous android 10 malheureusement... (j'ai vu trop tard qu'il fallait le retrograder) J'ai bien réussi à le déverrouiller et le programme d'installation sous ubuntu 20.04 semblait se dérouler normalement mais blocage à Waiting for device... Adb is scanning for device.
L'appareil est bloqué sur la page d'ammorçage d'Android. En maintenant power et son- il boot sur Fastboot mais impossible de l'éteindre.
Que faire ? L'un d'entre vous a-t-il une solution ?