people say not to use videos but i used if you already tried to mod it delete all of the files you put on the boot9strap and luma3ds and put in all the files he says to put in (im just trying to be helpful to others bc i have nothing else to do while im on summer break)
sense it is modded you can send it to nintendo you might need a screen replacement what model do you have old or new? (im just trying to help people on the internet bc i have nothing else to do)
depending if its old or new check its warrenty and make sure its not modded (if it is idk) send it to nintendo and they can fix the motherboard if its out of warrenty go to like a repair shop or something oh and maybe plug it into a computer with a adapter for the 3ds or if you backed it up you...
what 3ds do you have if its a new 3ds watch this vid and if you dont know what model you have check if you have the c stick the white thing then its new if not go to 3ds.hacks.guide