You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Can you please help me to book a plane from IAD to reach ORD immediately?

ASSISTANT: May I know your travelling dates?

USER: My preferred dates are on July 30th to Aug 1st.

ASSISTANT: Can I know your connection limit?

USER: Yes, I prefer it.

ASSISTANT: Do you have any other preference?

USER: I would like to return in morning time.

ASSISTANT: May I know your name?

USER: Sure, my name is Emily Lewis.

ASSISTANT: Sorry, no flights available on your route.

USER: No issues, thank you.

ASSISTANT: Thank you for reaching us.