You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you now?

USER: Can you help em in booking a flight ticket to SFO from IAD in May month?

ASSISTANT: Ok, may I know your trip dates?

USER: Sure, my trip dates are May 13 and May 15.

ASSISTANT: Do you need a connecting flight?

USER: I need single connecting flight for my journey.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: May I know your name?

USER: Yes, I am Michelle Green.

ASSISTANT: Sorry, no flights are available for your journey.

USER: Not a problem, anyways thank you for the information.

ASSISTANT: Thank you for choosing us.