This might be better solved in the Trader Support forums...
I really don't know what advice to give you on that, I know international orders can be so fussy sometimes, but you also don't want to just sit back and let your package be out there for weeks overdue with no contact from the seller... Perhaps the seller is out of town until after the New Year, but that's really poor seller-behavior, I mean, knowing you had packages out there that could potentially still be in the mail through the Christmas holiday... I mean at least once check your eBay to see if anyone has an issue (I mean, mine's hooked up to my phone, if I get a message, it alerts me, I can answer it in a few seconds, even just to say - Sorry I'm out of town will respond ASAP - or /something/!)
I suppose you could open an Item Not Received case? (That's a thing, right?) I mean, if it's still in the post, I'm not sure what they can do but, without a response from the seller, it's very hard to know one way or another! Sorry for your frustration, I hope your package arrives soon!