Yes, I have neogeo.zip in the same folder as my roms. I changed all my roms to uncompressed ones and now I'm getting
EDIT: nevermind, for some reason it's working fine after restarting my 3ds. Thanks! For people that gets the same problem make sure to get uni version of neo geo bios and make...
I've tried the rom on MAME PC and it works without problem so I don't think that's the case. The roms are also downloaded from archive . org. I'm guessing it's the bios? Mine is 1556 kb. It works on my pc though :/