Not quite sure what you mean, but when an item sells, the buyer pays the item price and the price you have there on the listing for the postage
You then use the money to pay for the postage.
You will always receive a lower amount when paid, and it may look like the postage price was not paid, but this is eBay's seller fees of 12.8% plus 30p per transaction, being taken.
They are taken the second the item sells, and sometimes are very similar to the postage price of the item.
