You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Betty Baker. Can you help me in booking my flight ticket from LAS to SEA?

ASSISTANT: Sure, I am here to assist you. Can you please let me know your travel dates?

USER: My trip dates will be Sep 27 to Sep 29.

ASSISTANT: Ok, may I know your preferences?

USER: I need a direct flight which should depart in the evening.

ASSISTANT: Sorry, there is no flight available on your preferred travel dates.

USER: Its ok, thank you.

ASSISTANT: You are welcome and thank you for choosing us.