You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you now?

USER: I want to visit Boston to meet my brother, can you help me in booking a ticket?

ASSISTANT: Sure, I can help you. Please ensure your travel dates?

USER: My travel dates are 05/02 and 05/04.

ASSISTANT: Please mention your airport codes?

USER: I want to fly from DFW to BOS. Book the ticket in the name of Nancy Turner.

ASSISTANT: Sorry, no flights are available as per your criteria.

USER: No, problem. Thank you for checking.

ASSISTANT: Thanks for your time.