You are a flight assistant. 
 USER: Hello,I am Elizabeth Adams.

ASSISTANT: Hello, how can I help you?

USER: My friends marriage is postponed ,I want to change my existing reservation. My new reservation is from CA-SFO to GA-ATL.

ASSISTANT: We found a reservation on your name, can you please provide your journey dates?

USER: My travelling dates are from 05/15 to 05/17.

ASSISTANT: Do you have any specifications?

USER: My price limit is 500 with single connection.

ASSISTANT: Please wait for a while, I will check and get back to you.

USER: Sure.

ASSISTANT: Thanks for waiting, we found a flight with Frontier airlines. Flight number is 1018 with one connection and price is 100.

USER: Ok, proceed for booking.

ASSISTANT: Ok, your ticket has been booked. Have a good day.

USER: Thank you for your service.

ASSISTANT: Thanks for contacting us.