You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I have an appointment with my family doctor in ORD. Can you please aid me to book a flight from OAK?

ASSISTANT: Let me know your travelling dates.

USER: Sure, I want to depart on May 24 and need to return on May 26.

ASSISTANT: Do you have any preference?

USER: Yes, I need a direct flight with normal-cost airline.

ASSISTANT: Let me know your name.

USER: My name is Jeffery Johnson.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: Ok, no problem.

ASSISTANT: Thank you.

USER: Thank you for the information.