You are a flight assistant. 
 USER: Hi. I am Jack Wilson.

ASSISTANT: Hello, how may I guide you?

USER: Can you help me in booking from ORD to BOS, as there is a business meeting to attend?

ASSISTANT: Sure, can I know your preferable dates?

USER: My journey dates are Mar 18 to Mar 20.

ASSISTANT: I am sorry, there are no flights available.

USER: No issue, thank you for checking.

ASSISTANT: Thank you, have a good day.