Maybe she accidentally sent the same comment five times, it's easy to do, if you click the submit button repeatedly your comment shows up several times and triggers the anti-spam auto block, if so, she'll be back in about 24 hours (or sooner if the F4 realise that it was a mistake). Another way might be that she has a sibling using the same computer for Fanpopping, when they find out that there is more than one user from the same IP adress, they automatically block all users on that computer. If you want to find out, just click "Contact Us" at the bottom of the page. The F4 should hopefully reply quickly enough and tell you why she was banned.