Hi Anya, Welcome to ATP!
Ebay is always an iffy choice for buying plants. If you order seeds, I can almost guarantee you won't get what you paid for. It looks like a Peony but obviously not what you expected. I have ordered plants from Ebay with success but,
1. Read all reviews and look at the ratings
2. Don't order from anyone outside the U.S.
3. Don't order from anyone who is not a nursery (ie: Has a mixed inventory - they are selling peonies but also used tires, sporting equipment and subscriptions to Life magazine...)
If you purchased with PayPal or a major credit card, you do have some recourse. Lodge a complaint with the seller and the credit card company and check the return policy.
Photos are always good.
Daisy