formatting isnt the same as factory resetting, the 3DS doesn't really do anything like that. if that's what your goal to "Fix" DS Mode was
@lolypopmaster11 at this stage now its hardmod or NTRBoot (seedminer wont help you since TWL Mode is broken for you. ) there is No free option past 11.3 for CFW, (you were on "Userspace Hax" which just means homebrew only and is quite limited in permissions and system functions they could call, installed CIAs wouldnt really work w/o Sigchecks Disabled, (that which requires Full CFW)
since you had been using Soundhax for Homebrew loading and not as an full CFW entrypoint, you had to of been on no higher than 11.3, and you updated past the point of no return for free anyway. a usable NTRBoot card will average between 15~25 + shipping depending what site you use and what card you get. not to sound harsh but you kinda did F* up. and before you say "i want only homebrew and not CFW, i dont want to get banned. " Dont kid yerself with such a fallacy. by Modifying your system even to use unsigned code in such where things like Soundhax (it alone and other userspace entrypoints) Still puts you at a small risk albeit a likely "Smaller" one than full cfw users are, this isnt like the PS2 Xbox OG, Wii Days. where modified devices could get away with it. there's always a risk with these newer systems (360/PS3/PS4/Xbox One/3DS/Switch) the moment they are modified.. want to have homebrew n Emulators and not worry about banning? get a second system mod the first keep the second "Clean"