1. Disable the GameShark: If you are using a physical GameShark device, you can disable it by turning it off or removing it from the cartridge slot.
2. Reset the game: Press the reset button on the Game Boy Advance or Game Boy Advance SP to restart the game. This should clear any active GameShark codes.
3. Check the game version: Make sure you are playing the correct version of Pokemon Emerald. Different versions of the game may have different GameShark codes, and using the wrong codes could cause problems.
4. Use a save editor: There are various save editors available for Pokemon Emerald that allow you to edit the game save file and remove any applied GameShark codes.
It is important to note that using GameShark codes can corrupt your game save or cause other problems. If you are experiencing any issues with your game after using GameShark codes, it is recommended to delete the game save file and start over.