You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself David Hall.

ASSISTANT: How can I aid you?

USER: I want to visit  Denver Botanic Garden can you please help me for booking a flight ticket.

ASSISTANT: Sure, can you please provide your nearest airport codes of journey?

USER: My source airport code is IAD and my destination airport code is DEN.

ASSISTANT: May I know your planned dates of journey?

USER: I am planning to travel on 06/12 and again I will be return back on 06/14,.

ASSISTANT: Wait for a while please.

USER: Sure. Please check for the direct flight.

ASSISTANT: David Hall, there is no flight available based on your requirement of 0 connection limit on this route.

USER: No issue I will choose another way. Thank you for the information.

ASSISTANT: Thank you.