You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: I am planning to travel from OAK to LAX, help me in booking a flight?

ASSISTANT: Can I know your depart and return dates?

USER: My travelling dates are May 11 to 13.

ASSISTANT: Can I know your connection limit?

USER: I prefer single connection flight.

ASSISTANT: Do you prefer an economy or business class?

USER: Any class is ok for me.

ASSISTANT: Can I know your name, please?

USER: I am William King, I prefer normal-cost airlines.

ASSISTANT: Sorry, there are no flights available.

USER: That's ok, thank you.

ASSISTANT: Thank you for opting us.