You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Larry Davis.

ASSISTANT: How can I assist you today?

USER: Please book me a ticket from PHL to OAK to meet my family.

ASSISTANT: Sure, I can help you with that. May I know your planned travel dates please?

USER: I have planned to travel on 08/17 and 08/19.

ASSISTANT: Ok, may I know your class preference please?

USER: I am ok with any class but i prefer normal-cost airline.

ASSISTANT: Ok, do you have any other specifications?

USER: I need a halt.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Sorry to inform you that there are no flights available for you on those dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.