You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I would like to travel from BOS to SFO, can you please help me in flight booking?

ASSISTANT: Sure, please provide your connection limit.

USER: I need a single connecting flight.

ASSISTANT: Ok, May I know your journey dates?

USER: I want to fly on Sept 19, return on Sept 21.

ASSISTANT: Ok, Do you have any class preferences?

USER: No.

ASSISTANT: Ok, Is there any other preferences?

USER: No.

ASSISTANT: Thank you for providing details, we did not find any flights with your given details.

USER: No problem, thank you.

ASSISTANT: May I know your name?

USER: My name is Joseph Wilson.

ASSISTANT: Thank you for approaching us.