sims 3 serial code has been used

[Elisif]

I bought a copy of "The Sims 3 two worlds" containing two different CD's, one with Monte Vista, which I had no problem installing and the serial worked just fine, and one with Hidden Springs which failed to install.

When I tried to install Hidden Springs, it claims that my serial has already been used. 

What do I do?

[Andromache2013]

Look here: http://answers.ea.com/t5/The-Sims-3-Store/Guide-Sims-3-Store-Worlds/td-p/1589911

[Elisif]

I am sorry to say that this did not help me at all

[Andromache2013]

Okay. I'll try help you more.

• If you go to your Sims 3 account and open your purchase history - does Hidden Springs appear there as well as Monte Vista? 
• Have you tried redeeming the codes at the Sims3.com? 

The two of them are worlds - not games, which makes trying to register them via Origin, give the invalid serial code message.