You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Can you please book a ticket from DTW to DFW to go for shopping?

ASSISTANT: Can I know your travelling dates?

USER: My travelling dates are Apr 6 and Apr 8.

ASSISTANT: Please let me know your preferences?

USER: I don't have any other preferences.

ASSISTANT: May I know your name please?

USER: Sure, I am Barbara Turner.

ASSISTANT: Please wait.

USER: Ok.

ASSISTANT: Sorry, no flights available on your route.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for choosing us.