Wrong Item recieved

"Won" an auction with "buy it now" a german Ebay-shop.
It was a Lian-Li Notebook cooler, bought for 34 Euro plus 6 Euro for shipping.
Now I have recieved the package, but it contains a Lian-Li PC computer case.....
What do I do ?
Have contacted seller and explained to him, that it will cost
more to return it, than I paid for the cooler. And I haven't
recieved the cooler yet.

Regards, Kim

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