Here's how it's supposed to work: http://answers.ea.com/t5/The-Sims-3/Information-How-to-Register-The-Sims-3/td-p/387162/jump-to/first-unread-message
If the codes are not working, you need to contact Customer support.
They can be found here: https://help.ea.com/contact-us
Choose a category, a game and a platform for the contact options to show up.
If live chat is gray, change your country to US and make sure you're on US Business hours. It might also gray because they're very busy. Try later.
See this post if you have trouble with the site: http://sims3.crinrict.com/en/2012/10/how-to-contact-ea.html
