You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you at this minute?

USER: Please help me to book a flight ticket from DEN to LGA.

ASSISTANT: Ok, I am here to help you with that. Can I know your planned trip dates?

USER: Sept, 5 and Sept, 7 are my trip dates.

ASSISTANT: May I know your good name?

USER: Rebecca Allen.

ASSISTANT: Do you have any other requirements?

USER: I am looking for connecting flight.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry to say that, there are no flights available based on your travelling dates.

USER: That's ok, thank you.

ASSISTANT: Thank you for approaching us.