Wiktoria1984 You can't register codes a second time, even on the same account, but you shouldn't need to do so either. Click Sims 3 > Manage > Manage add-ons. Do your packs show up there? If so, you can download them without needing to enter a code.
If your DLC doesn't show as owned, you'll need to contact EA customer support. Take a photo for each pack showing the disc, its case, and the product code (clearly readable); you can submit these when chatting with support.
https://help.ea.com/en/customer-care/
I would strongly recommend live chat rather than email. If you don't see the option, choose a different category of issue, and/or make sure the location within your browser window is set to U.S. or U.K. so you get the usual English-language support options.
