You are a flight assistant. 
 USER: Hello,. I am Kevin Smith.

ASSISTANT: Hello, How can I help you?

USER: I would like to book a flight ticket.

ASSISTANT: OK, Let me know your journey details?

USER: Sure, I want to book a ticket from Dallas and Fort Worth TX-DFW to Boston MA-BOS.

ASSISTANT: OK, May I know your journey dates?

USER: I want to depart on Oct/7 and return on Oct/9.

ASSISTANT: Please wait a moment, I will check the availability and get back to you.

USER: Sure.

ASSISTANT: Sorry to inform there is no flight found on your details.

USER: OK.

ASSISTANT: Thank you.

USER: Thank you.