Hacking Help my 3DS LL is semi bricked I think?

[Spider_Man]

Hi,

I have a 3DS LL which I downgraded years ago so it could run Gateway 3DS card.

I have had no problems with the console until today. When I power the console on, nothing happens, both screens are black.

Problem I have is I cant remember exactly what I did years ago, I do know that it is not running CFW, I think by looking at my SD card that its using MenuHax.

How I would normally boot my console would be Press and Hold Dpad Down button which would take me to Homebrew Loader, from there I would select Gateway then the console will boot and Gateway card is working.

If nothing is pressed on boot, the console will boot as normal.

I have a backup of my NAND on the console SD and on my laptop.

I am wondering if it is possible to fix my 3DS and get it working again, ideally id like to keep it how it was using Gateway and not CFW if thats possible.

EDIT:
I have learned that the console is softbricked and able to enter the recovery mode which installs the latest firmware, but it wont let me connect, gives error code 003-2101, not sure how to fix this and cant understand what else is said on the console with it been Japanese.

Thanks