Are you sure this is from an eBay seller?

If you have purchased some recent items from eBay,  checkout those sellers,  they may just have posted to the wrong buyer.

Click on the seller's listings,  then down the left sidebar click on Sold.  If you find the item there, send that seller a message  that you have received their item in error,  for them to send you enough money to cover a fully tracked return postage to return the item back to them.

Do not be fobbed off with sending to the correct buyer, it goes back to the seller.

If this is not the case, and no one else in your household knows of this purchase,  google Brushing Scam see if that applies here.

@denise67676 

Did it have your name on?

Sometimes sellers send the wrong item in error.  Could it be from a seller you have ordered from and you are waiting for an item and they have sent the wrong thing?

If you are sure it was not intended for you, it could be a brushing scam which seems to have resurfaced or, if it is low cost item, could it be a return that a buyer has sent back and the seller is using a random UK address (yours) rather than paying for an item to be sent back overseas?