You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am planning to visit Houston, can you please book me a ticket from DTW to IAH?

ASSISTANT: Sure, please mention your travel dates.

USER: My planned dates of journey are Nov 15 and Nov 17.

ASSISTANT: May I know your name?

USER: My name is Jeffrey Campbell.

ASSISTANT: Do you have any preferences?

USER: I prefer direct flight for this trip.

ASSISTANT: Sorry, no flights are available on your journey routes.

USER: Ok, not an issue. Thank you for providing information.

ASSISTANT: Thank you for choosing us.