If the package you received had the same tracking number you were given by eBay… then you should file a ‘return request’ from your Purchase History giving the reason ‘Item doesn’t match description or photos’.
If the seller doesn’t refund you OR provide a prepaid shipping label to return the empty package within 4 days … then your next step is to go back to the open request and ask eBay to ‘step in’.
I realize the procedure might sound strange … but this is how you have to navigate eBay’s automated computer system.