You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: I am Lisa Hall, want to book a flight ticket to Atlanta with price under 5000. Can you help me with it?

ASSISTANT: Ok, may I know your trip dates?

USER: Trip dates are 08/21 and 08/23.

ASSISTANT: Ok, may I know your travel codes?

USER: Travel codes are BOS-ATL.

ASSISTANT: Sorry, no flight found with your dates.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thank you.