ROM Hack Backup Pokemon Y save data?

[ntdat237]

I bought my 3DS and GW last summer. Since then, I have updated my emuNAND one time (that one wasn't succesful, I lost my pokemon Y save). With my old emuNAND, I can't play games like Azure Striker Gunvolt or Pokemon ORAS, etc.... Now I want to update it again, but the problem is the save data of pokemon Y. I heard its save is in emuNAND, but I don't know how to backup it Please help me