The seller has played you for time, giving excuses and promises which were not kept, and now you are well over the time to claim a full refund for item not received under eBay's 30 day MBG, Money Back Guarantee policy.
You must always ignore these false promises, don't listen to a seller's excuses, and remember to open a case within 30 days of the item's last estimated date for delivery.
Nothing eBay can help you with now, turn to your payment provider you should just be in time to claim there.
@dais_5415