You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Jonathan Green, want to travel from IAD to MSP. Please help me in booking my ticket.

ASSISTANT: Sure, when you like to travel?

USER: Sure, my travelling dates are from 08/17 to 08/19. Please search for a direct flight.

ASSISTANT: Sure, please wait a minute.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no flights available.

USER: It's ok, thank you for your help.

ASSISTANT: Most welcome.