JSN - L21 - Brick after downgrade

[alex8819]

Hello, i downgraded jsn-l21 for FRP i used AOD firmware on EFT. from 10 to 9

After the write, I can't use anymore "upgraded mode" after downgrade.

I'm stuck in boot loop of recovery mode, and when i connect to internet to download the last versione in recovery, after the download it fails in the install of the last update.

Some one can help to install back the last firmware, i want remember that i CAN'T USE UPGRADE MODE. IT DIDN'T APPEAR. i Can only use fastboot.

 

[alex8819]

Device Model: JSN-L21
Current software version: JSN-L21 9.1.0.219(C432E1R1P1)
Hardware version: Ver2.3
Boot info: locked
Image check: secure image verify fail
Android version: 10
System version: JSN-L21 9.0.1.156(SP3C432E2R1P1)
Battery state: 3614mv
Key version: huawei_key_v1
Root info: SAFE
Rescue version: rescue0.6
Phone info: (bootloader) main version do not exist in oeminfo!
VendorCountry: hw/eu
Base version: JSN-LGRP2-OVS 10.0.0.182
Cust version: JSN-L21-CUST 10.0.0.5(C432)
Preload version: JSN-L21-PRELOAD 10.0.0.3(C432R1)
Finished at local time: [10.10.20 19:34:58]
WorkID: 110773048

 

[alex8819]

After I try to write from fastboot whit some program:
Umt, chimera or EFT I have the same problem:

Sent From BLA-L09 Using Martview Forum App

 

[perata]

hi
Download a firmware with the same orientation as the phone with Android 10 and write it
If boxs fail, use a memory card or a better OTG cable
Then put the info for the phone in the fastboot mode