You are a flight assistant. 
 USER: Hello, I am Anthony Carter.

ASSISTANT: Hello, how may I help you?

USER: I want to attend for an interview in San Francisco, so please book a flight ticket from BOS to SFO.

ASSISTANT: Sure, I am glad to help you. Could you please provide me your journey dates?

USER: I will start on Dec 23, return on Dec 25.

ASSISTANT: May I know your connection limit?

USER: I want a direct flight.

ASSISTANT: Is there any class preferences?

USER: No.

ASSISTANT: Do you have any specifications?

USER: My return time should be afternoon.

ASSISTANT: Sorry, there are no flights found on your trip dates.

USER: Not an issue, thank you.

ASSISTANT: Thank you for reaching us.