Stranger ... Very stranger ...
Anyway ...
If it would be a 5X the rom Is completely different because it use a MIUI and not Android One (like Mi A1 does) ...
The MIUi forMi 5X are stored here:
http://www.miui.com/getrom.php?r=332&m=yes&app=false
Are you sure that pushing pwr button a long does not switch off ?
In this moment I don't know how exit from this state that looks as a softbrick very probably because we have used a ROM addressed to Mi A1 on 5X ...
Inviato dal mio Mi A1 utilizzando Tapatalk
been holding the power button only for at least 2 minutes and than together with volume up and volume down and absolutelly nothing .
So im going to google how to get out of this state.