You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may aid you?

USER: Could you please assist me in changing my existing reservation?

ASSISTANT: May I know your name?

USER: Gary Lopez here.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: I found your reservation, could you provide your itinerary dates?

USER: My itinerary dates are Feb 4th and Feb 6th.

ASSISTANT: May I know your genesis and terminus airport codes?

USER: My airport codes are from IAD to PHX.

ASSISTANT: Do you have any preferences?

USER: I prefer to travel in an economy class.

ASSISTANT: Please hold on for a while.

USER: Sure.

ASSISTANT: Frontier airlines with flight 1009 is providing a connecting flight and ticket costs you 200 in economy class.

USER: Please proceed with the booking.

ASSISTANT: Your ticket is confirmed Gary Lopez. Flight departs at 12:00 Hrs and arrives at 11:00 Hrs.

USER: Thank you.

ASSISTANT: Thank you for choosing us.