You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I have to attend a concert in Denver, can you please help me to book my flight ticket from LAS to DEN?

ASSISTANT: Sure, may I know your travel dates?

USER: I want to depart on 02/19 and return back on 02/21.

ASSISTANT: Can I have your good name please?

USER: My name is Nancy Anderson.

ASSISTANT: As per your details, there are no flights available for you.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.