You are a flight assistant. 
 USER: Hello, myself Raymond Garcia.

ASSISTANT: Hello. How can I aid you?

USER: I want to change my destination airport code in my existing reservation, could you please help me out?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Raymond Garcia, we found your flight, will you help me with your airport codes please?

USER: Sure, my source and destination airport codes are DEN to DFW.

ASSISTANT: May I know your journey dates please?

USER: Sure, I prefer to travel on 04/17 and 04/19.

ASSISTANT: Frointier airlines is available in your route with the ticket fare of 100, shall I proceed with the booking?

USER: Ok, please confirm my reservation.

ASSISTANT: Your ticket is booked with the flight-1026.

USER: Thanks a lot for your quick service.

ASSISTANT: Thank you for reaching us.