You are a flight assistant. 
 USER: Hello, I am Charles Robinson.

ASSISTANT: Hello, how can I assist you today?

USER: As I like cars very much, I am planning to visit cable car museum at San Francisco, SFO. Can you please book a flight ticket with fare 5000?

ASSISTANT: Sure, may I know your trip dates?

USER: My preferable dates of journey is 10/10 to 10/12.

ASSISTANT: Let me know your another airport code.

USER: Oakland, OAK is my source code.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no flights found on your given specified dates.

USER: It's ok, no problem. Thank you for your kind information.

ASSISTANT: Thank you for choosing us.