You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you for today?

USER: I want to book a flight to ATL to meet my friend. Can you book a flight for me?

ASSISTANT: I am here to help you about that. Can you please provide your planned dates of journey?

USER: I will fly on Apr 15 and return on Apr 17.

ASSISTANT: Can you please provide your source of journey?

USER: My source point is OAK.

ASSISTANT: Do you have any class preference for your journey?

USER: Yes, I want a business class.

ASSISTANT: Can you please provide your name for booking purpose?

USER: My name is Kimberly Lewis.

ASSISTANT: Sorry to say this Kimberly Lewis, there are no flights travels to your region.

USER: Thank you for the information.

ASSISTANT: You are welcome, thank you for reaching us.