You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I provide assistance to you?

USER: My name is Christopher Allen.

ASSISTANT: Ok.

USER: I am looking to book a flight ticket to meet my friend in Philadelphia. Can you help me for booking a flight ticket from HOU to PHL?

ASSISTANT: Sure, we are here to help you.

USER: My travelling dates are Nov 09 and Nov 11.

ASSISTANT: Do you prefer any halt in between your journey?

USER: I need a single connecting flight in my journey.

ASSISTANT: Is there any other preferences?

USER: My return time should be morning.

ASSISTANT: Ok, please wait for a moment.

USER: My departure time should be afternoon.

ASSISTANT: Sorry, no flights are available as per your requirements.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.