Did you make sure you failed i think twice and then your sister says its a 3 digit code or something and then try the codes again? Thats what i had to do when i used every codeI have tried EVERY single code in the walkthrough at least 20 times for the computer and none of them work. Every time it says incorrect code, I just hit back and try a new number but with no success. I'm going to tear my hair out.