You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Anthony Campbell.

ASSISTANT: What type of help do you need from our agency?

USER: I need to go Denver to deliver a lecture over there so please help me with flight ticket booking from New York city.

ASSISTANT: Sure, I will help you with that. May I know your preferable airport codes?

USER: Thank you. I  would like to travel from JFK to DEN.

ASSISTANT: Is there any preference related to connection limit?

USER: Yes, I am looking for single connecting flight but direct flight is also fine with me.

ASSISTANT: Ok, which class do you prefer to travel?

USER: I would prefer business class this time because of some health issues.

ASSISTANT: Can you please mention your planned travel dates?

USER: Sure, I have planned my travel dates as June 02 and June 04.

ASSISTANT: Sorry to inform you, the business class flight tickets are sold out on the dates you have provided.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: My pleasure. Thank you for reaching us.