I seldom have a quantity of more than one of any item, so I wasn't aware of this problem until it happened.
A buyer bought a quantitiy of two, the number I had listed, then immediately clicked the Buy Now button and paid the total amount listed on what appears to be an invoice generated by eBid. I was not involved in the transaction at all.
Unfortunately, under US Postal Service rules, two of the items weigh too much to use First Class Mail. So eBid could not calculate the amount of postage for two items, instead charged for one and sent me an email telling me to generate a second invoice for the correct remaining amount of postage due.
Unfortunately, when I select "Send invoice to buyer" I can only get the incorrect one that was apparently generated by eBid, and I can't remove anything that is filled in.
By the time I got eBid's email, the buyer had already paid the incorrect amount. I sent an email and she said she'd be happy to pay the extra postage, but she doesn't know how to do that without an invoice. Which I cannot create.
May I make a suggestion? It is very, very easy for a seller to credit the buyer for overpaid postage after the fact, because we have access to the buyer's PayPal account. In the future, if a buyer buys two of an item . . . DOUBLE THE POSTAGE AMOUNT . . . and notify the seller that the correct postage has to be calculated and the overpayment credited to the buyer.
I'll just pay the extra postage for this one.