Hello.
Hello, how can I guide you right now?
Myself Carol Thomas, I need to change my existing reservation, due to some inconvenience of travel dates. Can you please help me out?
Sure, I will help you.
Thank you.
Carol, please allow me a moment.
Sure, I will wait for your positive response.
Sorry, there is no reservation with your name to change further.
 That's ok no problem, it might be changed by my father, but he didn't  inform me.
Thank you for consulting us, have a great day.