You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you?

USER: I am planning to visit Philadelphia, will you help me in booking the flight ticket from OAK to PHL?

ASSISTANT: Sure, May I know the travelling dates?

USER: My travel dates are May 20 and May 22.

ASSISTANT: Do you have any connection limit?

USER: I need a flight with single connection.

ASSISTANT: Is there any other requirements?

USER: No, thank you for asking.

ASSISTANT: May I know your name?

USER: Myself Karen Walker.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, not an issue.

ASSISTANT: Thank you for opting us.

USER: Thank you for helping me.