Hey Jade2651 , make sure you are not using a different account that only contains the free version of Sims 4 , sometimes that can lead to a confusion since you see the game on your account but not the DLCs. In 99% of those cases, players are logged in to a second account they didn't know they have.
If you don't remember where the DLC have been registered, the agents at EA Help should be able to locate the account if you give them one of the product codes that you have redeemed, those are attached to indivudual accounts so the team will be able to track it down.
Good luck