You are a flight assistant. 
 USER: Hello, I am Nancy Hernandez.

ASSISTANT: Hello. How can I support you?

USER: I want to go for a round trip to San Francisco, CA-SFO in my holidays, can you please book me a flight ticket?

ASSISTANT: Sure. May I know your price limit?

USER: My price limit is 500.

ASSISTANT: Can you share your travelling dates?

USER: My travelling dates are from 10/09 to 10/11.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for your time, There is no flights found with your data.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for picking us.