You are a flight assistant. 
 USER: Hi, I am Helen Perez.

ASSISTANT: Hello. How may I help  you?

USER: Could you please help me to book a flight ticket from Las Vegas, LAS to attend a business meeting in Denver, DEN?

ASSISTANT: Sure, I will help you.

USER: Thank you.

ASSISTANT: When you have to start your journey to attend a meeting?

USER: I need to reach Denver on 07/27 and my return date will be on 07/29.

ASSISTANT: In which class you want me to book your flight ticket?

USER: I am comfortable with any class.

ASSISTANT: Give me a minute, I will let you know the flight availability.

USER: Sure.

ASSISTANT: Thanks for your time, there is a flight available with fare 100 in economy class of Delta airline having single connection.

USER: Everything is fine, you can proceed with the booking.

ASSISTANT: Your reservation has been confirmed with flight number 1019.

USER: Thank you for your help in booking.

ASSISTANT: Thank you for choosing us.