Hacking [Help] "You cannot use this Nintendo Network ID on this system."

[Stephano]

So the other day, I hacked a friend of mine's 3DS using a DSI downgrade. Once I installed A9LH, I formatted his 3DS (Which had my nintendo account because of the system transfer) and reinstalled a backed up nand that i made on my 3DS (The source 3DS). However, after doing this, I can no longer access the eshop like i could before the system transfer. When i check system setting and go to my ID settings, i get the error listed in the title. Does anyone know how to fix this?

 

[Skyshadow101]

What is the error code you get when you try to go to the NNID settings?

 

[wiiu more like pee u]

Your NNID will be dormant on his system and will be unable to be used on any other system unless you system transfer from his 3ds to yours. or call Nintendo to unlink the NNID from his system. Even if you restore your NAND backup from before, the NNID will still be unable to used on your system. A system format will not help.

 

[Cuphat]

Your NNID is on his console now. The guide warns about this. You either system transfer the opposite way to move all the NNIDs from his console to yours or contact Nintendo.