Adding additional items to an order after postage has been bought.

[mathemagic1970]

I have 3 of the same item for sale.
Someone has ordered and paid for one of the items. I have paid for postage but haven't yet posted the item.

The buyer has been in touch to ask if they can also buy the other two items and for me to put them in the same parcel to save postage.
The items are seller pays postage. How can I sell the other two without any postage involved? 

[**peaseblossom**]

Ths simplest way is to cancel the current transaction with buyer's agreement and relist all three together with one postage for the buyer to buy again.