You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I want to book a flight ticket from Denver DEN to EWR. Can you find a flight ticket for me?

ASSISTANT: May I know your travelling dates?

USER: Ok, my planned dates are on July 21 and return on July 23.

ASSISTANT: May I know your connection limit?

USER: I need a single connecting flight to travel.

ASSISTANT: Do you have any other preference?

USER: No, thanks for asking.

ASSISTANT: May I know your name?

USER: Ok, my name is Justin Edwards.

ASSISTANT: Sorry, no flights available on your route.

USER: Ok, not a problem. Thank you for your help.

ASSISTANT: Thank you for reaching us.