You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, please let me know how can I be a help for you?

USER: My name is Anna Hill, I need your help in booking a flight ticket.

ASSISTANT: Sure, it's my pleasure to help you. May I know your source and destination?

USER: I need my source as Chicago, IL- ORD and my destination as Philadelphia,PA- PHL.

ASSISTANT: OK, can I know your preferable date?

USER: Sure. My travelling dates are from 12/28 to 12/30.

ASSISTANT: Do you have any price and connection limit? Sorry for the inconvenience, no flight is available for you.

USER: That's fine. Thank you for the information.

ASSISTANT: Thank you.