You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: I am planning to attend a Tennis competition in Oakland OAK from Chicago ORD. Can you find a flight ticket for me?

ASSISTANT: May I know your trip dates?

USER: Ok, my planned trip dates are on Mar 25 and return on Mar 27.

ASSISTANT: Do you prefer any specifications?

USER: Yes, I want to depart in the afternoon time.

ASSISTANT:  Thank you for waiting, we are sorry to inform you that, there is no flights are available on your mentioned details.

USER: Ok, not an problem. Thank you for your information.

ASSISTANT: May I know your name?

USER: Ok, my name is Deborah Davis.

ASSISTANT: Thank you.

USER: Welcome.