With serial codes stating they're invalid, you most likely will have to contact EA, they can be found here: https://help.ea.com/contact-us/ask . For help with navigating your way around, see this: http://sims3.crinrict.com/en/2012/10/how-to-contact-ea.html
With registering codes on ORIGIN and not being able to find your code, etc please see here: http://sims3.crinrict.com/en/2013/09/how-to-find-your-serial-number.html
Please keep in mind that if you bought the game off Origin, it is AUTOMATICALLY registered FOR YOU! To get your accounts connected, simply use the same details as you use for Origin.
For problems with worlds, please see here: http://answers.ea.com/t5/The-Sims-3-Store/Guide-Sims-3-Store-Worlds/td-p/1589911
For more info, please see these links:
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