PBP won't boot

[alchemist]

Hi!

Yesterday, I rebooted my PBP and it did not boot again. The green power led is not on.

I have 2 power supplies, and I see that the red light is not lit with the one I used yesterday. I have created a support ticket for this defective power supply.
So it could be I drained the battery to 0%.
I plugged the PBP all the night to recharge the battery.

I tried to unplug the battery and use the bypass cable, long press on the power button, press the reset button, but no success.

I tried to boot a SD card but no success too.

Before this state, the OS on the eMMC and on the SDCard were working fine (Gentoo like all my PC and other ARM servers).

I don't have the official debug cable, but I can make one with a USB FTDI cable and a hacked jack cable.  Or do you have any reference I can use instead? or wait until it's available on the Pine Store?

I did NOT flash the SPI nor U-BOOT, they are working and I don't want to brick the boot process. I only did a repartition on the existing Manjaro, keeping the start offset of the first partition.

What operation can I do to unbrick it?

Thank you very much!

Kind regards,
Xavier