I ordered a book, the first sender mailed the book (with DC, even!) but forgot to mark it mailed. The system timed out the request and it rolled over to the next member. I wasn't paying attention and thought I was still on the first request! I have already gotten both books, but the first sender PM'ed me asking me to please mark it received. She must have not realized that she didn't mark it mailed when she got back.

I know that the help docs say that I don't have to mark the first book received if the first sender didn't mark the book mailed. How can I tell her (nicely) that I don't have to mark it received and am not willing to spend a credit for her forgetfulness?

You can just tell her that the next person mailed the book and you received it and include the info from the help-docs to back you up. If nothing else, it'll help her to remember to mark her books as mailed in the future.

I'd just copy/paste the appropriate Help Center files:

Scenario #1 (the most common scenario):

• You submit a request, which goes to Sender #1

• Sender #1 does not mark the book mailed before the deadline, but still mails the book.

• Then the request cancels and gets passed to Sender #2, who also sends the book.

• You end up with two copies.

  This situation (the requestor ending up with 2 copies of the book) is part of why marking a book mailed before the deadline is such an important part of the swapping process.

  The bottom line here: always mark your books mailed, so you don't become Sender #1!

In both Scenarios #1 and #2: When you receive 2 copies for a book after submitting only one request, you are not obligated to give a credit for the extra (canceled) copy.  You are obligated to mark the properly sent copy received.

• When you mark the book received from the active transaction on your En Route to Me tab on your My Account page, Sender #2 will get credit. 

• • Sender #2's transaction is the only active transaction for the book on your account page.
  • The transaction with Sender #1 moved into your Transaction Archive when it was canceled, as a canceled transaction.

• You are not obligated to give a second credit for a canceled copy of a book when you submitted only one request
  • You are also not obligated to send the book back (although this is a nice thing to do if the sender is a new member).
  • You are obligated to mark the book received that is on your En Route to Me tab on My Account.

I'd just say, per the Help Center, since you failed to mark the book mailed and I got 2 copies of it, I'm not obligated to give you a credit for this book.

Unfortunate situation.  As Sarah posted, the guidelines state that you are not obligated to mark both books received.  You have done nothing wrong, and therefore do not have to offer a second credit for the same book.

Ok, for the person who mails a book out and it has already timed out, don't they notice that the transaction has disappeared from their account page??  I mean, it disappears, right?  Because if I'm the requestor, it disappears from my page.  

Don't they get the feeling that something's wrong with this picture, and maybe it's too late for this transaction to happen now?

They do know. But are hoping you can either cancel the 2nd copy coming to you or that you will give them credit anyway.  Or they may not know that the system will auto reorder.

Plus, they get emails from PBS reminding them to mail the book and to log in to PBS and mark it mailed so they get their credit.

I sent her just what Sarah posted. I don't pay much attention unless it completely disappears from my screen as a requestor, but since it rolled over, it was still there, just in a different transaction. If the second copy hadn't already been on its way, I would have canceled it, but the second sender was super fast!

Thanks all!