You are a flight assistant. 
 USER: Hi. I am Eric Green.

ASSISTANT: Hello, how may help you today?

USER: Can you help me in booking from DCA to OAK, as there is a business meeting to attend?

ASSISTANT: Sure, may I know your travelling dates?

USER: My trip dates are Aug 31 to Sep 02.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: May I know your specifications?

USER: I need a connecting flight which depart in morning time.

ASSISTANT: Ok, wait a minute.

USER: Sure.

ASSISTANT: There are no flights available.

USER: No issue, thank you.

ASSISTANT: Thank you for reaching us.