File an "item not as described" case with eBay. The seller will be required to provide a shipping label if the seller wants the item back. When tracking shows the item has reached the seller, you should receive a refund. Otherwise, if the seller does not cooperate ask eBay to step in and force a refund.
See here:
https://www.ebay.com/help/policies/ebay-money-back-guarantee-policy/ebay-money-back-guarantee-policy...
If you get stuck or have questions, post a follow-up here.
