The Sims 3 activation code already used

Hello, so here is my problem. I received The Sims 3 for Christmas. I installed the game normally with Origin. Then I played it. Everything went well until yesterday when Origin asked me for the activation code again. I entered it, but it says the code has already been used. So, I uninstalled the game thinking it was an installation issue. I wanted to reinstall it, but Origin asks for the activation code again and still says the code has already been used. I contacted EA support by phone, but the wait time is too long.

Can you please help me?