Message the seller first as they won't see your post here.
Go right of the item in your Purchase History >> More Actions >> Contact Seller
Tell them of the missing items, hopefully they'll send those out for you, but don't wait too long.
You have 30 days from the item's last estimated date for delivery to open a case for a full refund. You then need to proceed this way:
You then go right of the item in your Purchase History, and from More Actions select Return this item, selecting the reason... Item Missing Parts or Pieces.
The seller has 3 days to accept the case, if they don't , you need to escalate on day 4, or within 30 days, and eBay will step in and force the refund.
If the seller wants the item back first, they need to pay for a fully tracked return postage. On receipt of their item they have 48 hours to refund you. Again, if they don't, you escalate the case.
Do not close the case early for any excuse or promise the seller may give, and do not forget to escalate.
@jbw548
