You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Shirley Hill.

ASSISTANT: How may I assist you today?

USER: I am planning to book a ticket to visit a new place at NY-EWR. Can you please help me out to book a ticket from CO-DEN?

ASSISTANT: Sure, I am here to help you with that but I need your travelling dates to search a flight.

USER: I would like to travel on Nov 13 and return back on Nov 15.

ASSISTANT: Do you have any specifications?

USER: Yes, I am looking for a normal cost flight.

ASSISTANT: Sorry, I could not find any normal cost flight for this route.

USER: That's fine, thank you for your service.

ASSISTANT: My pleasure.