What do I do? I have marked a book mailed when in fact when I went to my shelf I could not find the book.  I vowed never to do this again and here I am doing it.  Instead of finding the book first and then proceeding I have gone in reverse. I did PM the requester of my unforgivable mistake.  I do not know how to cancel the order now that I have marked it mailed.  I must have mailed the book to someone else in a deal and forgot to delete it from my shelf. I apologize again that this has happened.

Margaret, the Admin Team can cancel the transaction for you.  Go to the bottom right corner of any page, and under "community" click on "contact us."  Use the Feedback option.  And of course you'll find the book under the couch the next day. :-)