You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: Can you please help me to book a flight ticket from DTW to OAK?

ASSISTANT: Sure, I am here to help you with that. Can I know your planned trip dates?

USER: My travelling dates are Aug 3 to Aug 5.

ASSISTANT: Do you have any other requirements?

USER: I want to depart and return in the afternoon.

ASSISTANT: May I know your good name?

USER: Carol Mitchell.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: Sorry to say that, there are no flights available based on your travelling dates.

USER: No problem, thanks for your information.

ASSISTANT: Thank you for approaching us.