Freezing on picking up Pokéball

[AlexG123]

I'm playing a Pokémon Ruby hack (Snakewood), and in the beginning I need to pick up Pokéballs to get Pokémon. Whenever I do this, the emulator freezes and on the lower screen prints a message containing two smiley faces and the letter "I".
I'm using a New 3DS XL if that changes anything.