When I enter my Sims 3 product code it says ''This code has already been used''.

You're probably having trouble reaching a game advisor since it is Sunday.  I know they don't take phone calls then and their live chat support is minimal on Sundays.  

As for your game, I highly doubt you'll be able to get another code.  Newer versions of the game come with one code that can only be tied to one Origin/Sims account and the installation requires this one time code.  This is to prevent people selling their games without EA making any kind of profit.  Sorry.  

You definitely try returning it.

My guess is as good as yours, but I think it's been someone who was putting in random codes and hoping to get lucky, and they ended up getting yours for free. The only thing you can do is contact an administrator on Origin. If that doesn't work, you'll pretty much have to buy a new, unused copy to be safe.

I've also had this problem. I bought the Sims 3 at game stop a while ago and I've played it on my pc a good amount. Though I stopped playing it for a while. Then recently I felt the urge to play the game, but my origin account said I had to reinstall it. So I did then it said my code ha already been used. I have the box and everything. I can't even use my expansion packs any more either because I do not have my sims 3 installed. WHat should I do? 

Where are you reinstalling from ? Origin download or the DVD ? You don't need to register again just install from the account you have the game on.

I uninstalled the Sims 3 and my expansion packs. I tried to reinstall the Sims 3 but it says that the product code has been used and the game in not in my "my games" in my origin account. Any help or suggestions, pretty please?

I'm having the same problem!  Or at least similar. Though a lot of my other Sims 3 games that I had already installed before on a different computer were already on my origin account. I never registered my Sims 3 Supernatural game, now it's telling me that myproduct code is invalid. Could this really have been because someone else entered the same one? This is the same thing that is happening with the Sims 3 Into the Future game that I JUST got for Christmas. Like today. I got the disc from my mom, and instead of inserting the disc, I just registered the game and tried installing it off of my Origin account. 

Maybe I should go back to the beginning. I reinstalled all of the Sims expansions on my new computer, and every one of them was fine. Then like, three of them (including the one I just got for Christmas), when I clicked "Download" from origin, it said something like "It's already installed on your computer, go uninstall it from your computer and then re-download it from origin," though it isn't even on my computer at all to uninstall in the first place. When I inserted the Sims 3 Supernatural disc when first installing it on the new computer, it just would not come up! Which is why I tried the other route of registering it and downloading it from Origin. 

I am feeling very frustrated! Do I really need to go buy all these games online again so that I can get a game code? If so, then that is just plain ridiculous. I can prove that I have the original game and the code inside it, and also from my purchase history too! 

I went and found the lessage that it showed up for me whenever I tried installing some of my registered games from Origin:

"DLC Compatability Alert" 

It seems the base games for this DLC was not installed through Origin.  For The sims 3 Into the Future Limited Edition to work, You will first need to:

1. Select "uninstall now" below, locate the base game, and follow the on-screen instructions to uninstall it.

2. Donload and install the base game through Origin by selecting it in My Games and clicking "Download"

After that, you can download and play The Sims 3 Into the Future Limited Edition"

Only this game doesn't even show up in the "Add or Uninstall a Program" thing from my control panel when I actually did click "Uninstall now"

What's the answer???

It won't install because its used. EA most likely won't give you a new code, they'll just tell you to get a new copy. One copy per computer and thats it. The previous owner likely registered the game when he played it so it can never be installed on anything else but the computer with his account again.

You essentially just bought a rather expensive coffee cup coaster. ☹️

i am having the same problem. my old computer crapped out so i got a new one but the thing is when i tried registering my games to origin and/or the sims3 website it said i could not because the code was already used. i really dont want to buy new games again but if i have to i will but i kow people who have used the same dics in many computers and it has worked. can someone please explain to why this is happening...? thank you

did you downlaod orign to your new computer ? if so try log into the origin shortcut with the email and password you use for your ccount then right clcik the base game icon-downlaod let it updtae to wahtever updates it needs launcht he game make sure it works then download the next one launch paly rinse repeat