Hacking Trying to fix eshop error 022-2634

[Duckling]

I recently bought a 3DS from a friend and when I format my emuNAND with tinyformat and inject the emuNAND back to the SD Card it doesn't work.

I'm using my own NNID, i'm not sure I have to use his, but if this is the problem is there a way of removing his NNID from both my sysNAND and emuNAND completely?