Well, you could contact the seller, explain the error and ask if he had the right size in stock.
Then, if he agrees, you could send the item back to him, with Delivery Confirmation, and he can give you either a refund or a replacement, depending on your agreement.
The Delivery Confirmed shipment to Asia, where most of these are bought, runs about $40.
It's the price of a latte. Give it to a friend with the right phone or donate it to the church bazaar.