Even after doing that it still didn't work.You should always change the NNIDInfo. If you get caught using one NNID on multiple SecureInfo_A files, bad stuff will happen.
Also, I did that by accident earlier and my 3DS flipped out and crashed. So there's that.
I should add that I got banned from online cuz of Sky3ds and header problem(I guess my private header wasn't installed correctly) so maybe this method won't work.