If it asks for the code every time she tries to play, it's not taking the code. It should only ask for the code once, even if the game itself won't start.
Make sure there's nothing blocking your Internet connection, like a software firewall or "Antivirus Internet Suite" or some other thing. The game needs both your code and the Internet.
Also, check that the code isn't using capital O's instead of zeroes or vice versa -- or capital I's and ones. If the code has hyphens in it, try typing the code both with and without the hyphens.
If none of that helps, you'll have to get tech support through Viva Media.http://support.viva-media.com/
If you scroll down that page, there's a button for "Open New Ticket."
This is the kind of thing that can happen when people download an illegal copy of the game and use a key generator -- they steal a working key from someone who actually bought the game. Of course I don't know for sure that's what's happened, but it's a possibility.