Hello.
Hello. How may I assist you?
Can you help me in changing my existing reservation?
Sure, I am glad to help you and may I know your name please?
I am Karen Wilson.
Please give me a moment.
Sure.
 Thank you for waiting, I have checked in reservation list to change your ticket but could not find any reservation with your name.
Ok, no problem. Thanks for the information.
Thank you for reaching us, have a nice day.