She needs to restart her game, look it up on the internet that tells you how to re-start her nintendogs game.

You re-start the game by pressing X,A,B,Y,L and R right when the game starts up. It is in the manual. Also make sure she says it in the same tone every time. after she does that, she'll have too teach her dog sit. good luck!

i looked in the manuel and tried my best to say it at the same tone each time but it still
won t work.

restart your game by pressing abxyrl and get another dog

i think that if you restart the game and buy another dog it should work

You can restart the game and buy a new dog. But make sure you say it's name in the same
tone you said it in when it was learning it's name