Hello everyone.
I bought a japanese Xperia 1 III (Softbank version A101SO) with Android 12 and I've searched for the 13 update but it turns out Softbank didn't release Android 13 on this phone yet.
So I decided to flash the KDDI version to it (with newflasher) and it worked.
But the problem is I got a very weak signal, a battery drain and the 4G rarely appears (always H or H+)
I tried to come back to the old original firmware but the phone won't boot after the flashing process (rollback protection)
The phone has a locked bootloader and it says it can't be unlocked so I wonder if you have a solution for me because I lost all hope right know.
If I can just go back to its original firmware (Android 12 from Softbank) that's all that I need right know.
Thak you for your answers.
I bought a japanese Xperia 1 III (Softbank version A101SO) with Android 12 and I've searched for the 13 update but it turns out Softbank didn't release Android 13 on this phone yet.
So I decided to flash the KDDI version to it (with newflasher) and it worked.
But the problem is I got a very weak signal, a battery drain and the 4G rarely appears (always H or H+)
I tried to come back to the old original firmware but the phone won't boot after the flashing process (rollback protection)
The phone has a locked bootloader and it says it can't be unlocked so I wonder if you have a solution for me because I lost all hope right know.
If I can just go back to its original firmware (Android 12 from Softbank) that's all that I need right know.
Thak you for your answers.