Hi Geza,
I did a search to see if I might be able to help solve the problem. If you aren't able to register the key with the steps below, then you will need to contact EA support.
To register a game for the digital copy through Origin, you need to:
1.) Create an account at
http://thesims3.com/. If you already have an Origin account, use the same information to log in to the Sims 3 site.
2.) Log in to the account.
3.) Click the My Page link at the top of the page.
4.) Scroll to the bottom of the page and there will be a Register a Game link at the bottom of the left side of the profile page. Click the link.
5.) Enter the serial code for the game (the CD key) and click the Register button.
6.) The game will now show in the Origin client.
In order to download the game from Origin, you need to uninstall the disc version of the game. Then go in to the Origin client and log in (use the same ID and password you used for the Sims 3 website). Hover over your Sims 3 game in the My Games list and click the Download link to download and install the game.
If you need to contact customer support -
https://help.ea.com/contact-usChoose 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 EA's Help site:
http://sims3.crinrict.com/en/2012/10/how-to-contact-ea.html Hope this helps,
MrsFlynn