You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you at this moment?

USER: Can you aid me to book a flight ticket from IAH to SFO?

ASSISTANT: Sure, may I know your class preference?

USER: I prefer business class flight.

ASSISTANT: Ok, do you need any lay by in between the journey?

USER: Yes, I need a single stop over in between my journey.

ASSISTANT: When would you like to depart from IAH?

USER: I want to take off on Mar 17 and return on Mar 19.

ASSISTANT: Ok, Can I have your name please?

USER: Sure, myself Paul Parker.

ASSISTANT: At what time would you like to travel?

USER: I am fine with any time.

ASSISTANT: Do you have any airline preference?

USER: No.

ASSISTANT: There are no flights found on your requested dates.

USER: That's fine, not an issue. Anyway thank you for checking.

ASSISTANT: Thank you for reaching us.