You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Can you book a economy class ticket from ORD to IAH?

ASSISTANT: Sure, please share your planned travel dates?

USER: Mar, 27 and Mar, 29 are my planned travel dates.

ASSISTANT: Do you have any connection limit?

USER: I would prefer single connection.

ASSISTANT: Any other preferences?

USER: I need to depart at evening time.

ASSISTANT: Can I have your name please?

USER: Ronald Harris here.

ASSISTANT: Sorry, no flights found with your given details.

USER: That's ok, thank you.

ASSISTANT: Thank you for opting us.