You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: I am Emily Davis, want to book a flight ticket to Atlanta with price under 500. Can you help me with it?

ASSISTANT: Sure, Please mention your travel dates.

USER: My travel dates are 09/21 and 09/23.

ASSISTANT: Kindly share me your airport codes.

USER: Airport codes are IAD-ATL.

ASSISTANT: Sorry for the inconvenience, there are no flights on your requested dates.

USER: Ok, no issues. Thanks for the help.

ASSISTANT: Thanks for choosing us.