Ireland’s postal agency An Post is apologizing for returning a 3-year-old’s letter to Santa… marked “insufficient address.”

The BBC reports that apparently “Santa Claus, Santa’s Grotto, Lapland, The North Pole” wasn’t good enough — even though An Post delivered the letter from the little girl’s eight-year-old sister.

An Post says it successfully handled 140,000 letters to Santa this year, and is very upset about this one.

It offered to send a special letter to the three-year-old, but was turned down.