Instructions
Choose "Connect to Pokewalker" at the game's main menu. Hold "Down" and "X" plus "L" to reset the Pokewalker.
Press the "A" button to confirm the Pokewalk reset when prompted. Reset the Nintendo DS console using the corresponding button on the side of the device.
Press "Up," "Select" and "B" simultaneously at the title screen to reset the game. Confirm the decision when prompted with the "A" button.