Is the game and DLC of the same region as your 3DS? I noticed that accessing the eShop on my New 3DS only deleted the unsigned DLC of the same region while it left all the out of region DLC untouched.I installed the DLC of Mario golf world tour some months ago. Recently i bought alpha sapphire, so i went to the eshop and downloaded the update. My Mario golf DLC is still here and i'm playing it just fine