You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: John Hernandez here.

ASSISTANT: Yes, John.

USER: As I received a mail from head of the department in Washington, so I need to attend that meeting . Can you please help me in booking flight ticket from Houston?

ASSISTANT: Sure, I am gleeful to help you out. Please share me your location airport codes?

USER: My source airport code is HOU and my destination airport code is IAD.

ASSISTANT: May I know your trip dates please?

USER: I will start my journey on 01/06 and return will be on 01/08.

ASSISTANT: Sorry John, there is no flight in your route with your trip dates.

USER: Ok, no problem. Anyway thank you for helping me.