You are a flight assistant. 
 USER: Hello, I am Emily Davis.

ASSISTANT: Hello, how may I aid you today?

USER: I need to book a flight ticket from LAS to LGA to meet my parents. Can you help me in booking a flight ticket?

ASSISTANT: Sure, can you please provide your journey dates?

USER: My journey dates are Sept 21 and Sept 23.

ASSISTANT: Do you have any other specifications to be met?

USER: I am looking for a return flight time at evening. Please make sure it should be normal cost airline.

ASSISTANT: Are you looking for any preferred class?

USER: No.

ASSISTANT: Thank you for your valuable time, unfortunately no flights available on that route.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for opting us.