Dear Mary: How can I remedy an insult to my bookshop customers?

From Nicky Dunne, Heywood Hill bookshop

Q. A much admired actor rang our bookshop to send a hardback copy of Don Quixote, with an appreciative handwritten note, to a very distinguished fellow board-treader. Unfortunately we sent a children’s illustrated edition by mistake, thereby putting a backhand slice on what was meant to be a compliment. How can I make it up to them both?

A. Obviously you should send a complimentary copy of the real version – but don’t apologise too much. Actors have the most fragile of egos and you must not risk fomenting heightened paranoia. Instead blame the mistake on your intern, explaining that, since colouring-in books for adults have become fashionable, you have also had a run on children’s versions of the classics and your intern assumed that the children’s Don Quixote would be the desired version.

Mary Killen solves problems for Mary Beard, Nigel Slater and Nicky Haslam in her Christmas