You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: I want to meet my old friends, can you please book the ticket from PHL to IAD?

ASSISTANT: Sure, could you please share your departure and arrival day?

USER: I would like to depart from my source location on 26th June and I want to return back by 28th June.

ASSISTANT: Sure, could I have your name please?

USER: My name is Joseph Lee.

ASSISTANT: Ok, do you need direct or connecting flight?

USER: I prefer single connected flight to travel.

ASSISTANT: Ok, may I know your airline preference?

USER: I prefer major airlines only.

ASSISTANT: Ok, do you have any other specifications?

USER: Yes, I want to depart in the afternoon time and I want to return in the morning time.

ASSISTANT: Sorry, there is no flight on your requested travelling dates.

USER: Oh! That's ok, thank you for giving the information anyways.

ASSISTANT: You are welcome, have a great day.