Ok. Thank you very much! I will pick up on this in the morning.Your save file for that game is likely not in the right place.
https://3ds.eiphax.tech/private.7z
Make sure to extract (i.e. decompress) that file and place the /private folder in your sd card's root (beside boot.nds).
Edit: I've attached a zip of the two files that might give you trouble (because you have to install a Windows program to extract them).
You can open the SD_files.zip and put the files inside on the sd root.