answer: Edward Smith wants to book a flight to New York on July 21st but it isn't available, so he takes another flight on July 22nd.
documents: #Person1#: Hello, China Southern Airlines. Can I help you?
  #Person2#: Yes, could I make a reservation to New York on July 21st, next Friday?
  #Person1#: Sorry, there is no flight available on July 21st.
  #Person2#: That's too bad. What's the earliest flight available?
  #Person1#: I can give you a reservation on flight No CZ 387 on July 22nd.
  #Person2#: What about the fight schedule?
  #Person1#: It departs at 12:10 and arrives at 15:10 next day.
  #Person2#: Is it a non-stop flight?
  #Person1#: Yes.
  #Person2#: Sounds good. I'd like to take this flight.
  #Person1#: Would you prefer first class or economy class?
  #Person2#: Economy class.
  #Person1#: And your name, please?
  #Person2#: Edward Smith.
  #Person1#: Mr. Smith, you can get things fixed through our agencies in Guangzhou. Do remember to bring your passport with you.
  #Person2#: Yes, many thanks. Goodbye.
  #Person1#: Bye.