Newly purchased Pixel 3a won't let me downgrade Andoid to 9.

MrT10001

@kandjou DO NOT LOCK the bootloader, you may totally brick the device at worse or cause issues making it difficult to get back at least if you don't have Android on the device.

This is what I would do:

Put Android back on the device (the one that you installed to put UT on).
Set it up

Then, as Focal (20.04) is not working for you try Xenial Stable 16.04 which is regression and see if UT works from that. Use the UT Installer and select 16.04 (Stable) in the drop down.

kandjou

@MrT10001 Thank you @arubislander and MrT1000

I am think of giving up , it's so boooring (10 days... 10DAYS, it's enough, for me so complicated it is) although I am learning about amazing tools and trics

Thank you for your responses guys !!

Now : no valid slot to boot
I could reinstall Android V9 (the good one, about that : the installer says Google Pixel 3a/3a XL (sargo) but I have a 3a XL and they put the "bonito" https://developers.google.com/android/images#bonito)

There is always some problem

kandjou

@kandjou When I connect my phone to charge, the screen become crazy, impossible to select the icone I touch.

Cl : DON'T buy a Google Pixel 3a XL

Thank you for your time

bye