You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to book a flight from IAD to OAK to visit Comic-Con. Can you help me with booking?

ASSISTANT: Sure, may I know your name?

USER: My name is Anthony Phillips.

ASSISTANT: Can I know your travelling dates?

USER: I will fly on Jan 29 and return on Jan 31.

ASSISTANT: Do you have any other specifications?

USER: I need direct flight and normal cost airline.

ASSISTANT: May I know your class preference?

USER: I am fine with any class.

ASSISTANT: Ok, wait a minute.

USER: Sure.

ASSISTANT: Sorry, there are no flights available on your request.

USER: Ok, thank you for the information.

ASSISTANT: Thank you for choosing us.