You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you?

USER: I am Patrica White. I am planning to visit Golden gate bridge at San Francisco, SFO. Can you please book a ticket for me?

ASSISTANT: Sure, May I know the source code?

USER: Source code is Boston, BOS.

ASSISTANT: Please help me with your travel dates.

USER: My trip dates are 10/18 to 10/20.

ASSISTANT: Please wait a second.

USER: Sure.

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

USER: No problem. Thank you.

ASSISTANT: Thank you for availing us.