You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Melissa Wilson.

ASSISTANT: How can I help you?

USER: I am looking for a direct flight from BOS to ATL, can you please help me to book a flight ticket?

ASSISTANT: Let me know your travelling dates.

USER: Sure, my journey dates are July 12 and July 14.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: No problem, thank you for your information.

ASSISTANT: Thanks.