You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I guide you?

USER: I am Catherine Green. I am planning to visit Golden gate bridge in  San Francisco, SFO. Will you help me in booking a flight ticket on 03/16?

ASSISTANT: Sure, may I know your source point?

USER: Orlando, MCO is my source airport.

ASSISTANT: Do you need a return ticket also?

USER: I intend to return on 03/19.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry to inform you that there is no flight available on your dates.

USER: Ok, I will choose other airline.

ASSISTANT: Thank you for contacting us.

USER: Thank you for quick service.