You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: Can you please make my reservation from ATL to OAK?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: Sure, my travelling dates are Dec 18 and Dec 20.

ASSISTANT: Do you have any specifications?

USER: I need a direct flight.

ASSISTANT: Please provide your name.

USER: My name is Shirley Green.

ASSISTANT: Do you have any other specifications?

USER: No.

ASSISTANT: Please give me a moment.

USER: Sure, take your own time.

ASSISTANT: There are no flights found under your preferable details.

USER: That's ok, thank you for your information.

ASSISTANT: Welcome, have a great day.