You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I'm William Moore. I am planning to attend business meeting, can you please help me with booking a flight ticket?

ASSISTANT: Sure, please provide your trip dates to find a flight for you?

USER: Sure, I would like to take off on 07/13 and return back on 07/15.

ASSISTANT: Can I have your airport codes too.

USER: My source airport code is ORD and the destination airport code is SFO.

ASSISTANT: There is no flight for you according to your details.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thanks for reaching us.