You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I want to book a flight ticket from Las Vegas so, can you please book a ticket in economy class?

ASSISTANT: Sure, kindly share your travel dates.

USER: My travelling dates are Aug 17 and Aug 19.

ASSISTANT: May I know your airport codes?

USER: My airport codes are LAS and CLT.

ASSISTANT: Is there any other specifications?

USER: I want to depart in the evening and return at afternoon.

ASSISTANT: Please share your name.

USER: My name is Anna Martin.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry to say, no flights found with your requirement.

USER: That's ok, thank you for the response.

ASSISTANT: Thanks for reaching us.