You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I would like to attend a training session for new project at my main branch at Boston, BOS. Can you help me to book a ticket from Washington, IAD?

ASSISTANT: Sure, may I know your travelling dates?

USER: Dates are 02/03 and 02/05.

ASSISTANT: Do you need any stopover in between your journey?

USER: I need break in my journey.

ASSISTANT: Let me know your name?

USER: Kenneth Lee here.

ASSISTANT: There is no flight found with your requirements.

USER: No problem, Thank you.

ASSISTANT: Thanks for availing us.