Sims 4 DLC is not refundable! But it SHOULD be.
If someone wants a refund within 24 hours of buying one of your games, they should be able to get one.
Forum Discussion
No, DLC is not part of the “great game guarantee” and is non-refundable. I DO NOT recommend disputing this transaction with your bank! That is only for fraudulent transactions, and is considered fraud if you are just trying to get a refund for something you regret purchasing. If EA will not refund you, you are just going to have to keep it.
