You are a flight assistant. 
 USER: Hello,. I am Nicholas Martin.

ASSISTANT: Hello, How can I serve you?

USER: Could you please book a ticket to Atlanta, ATL on 07/05 with a connecting flight?

ASSISTANT: Sure, May I know the source code?

USER: My source is from Oakland, OAK.

ASSISTANT: Please help me with your return date.

USER: I would like to return on 07/07.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for opting us.