Hello.
Hello, how may I be at your service?
I want your help in changing an existing reservation, as my trip to visit White House got postponed.
Ok, may I know your name?
I am Emma Jones.
Ok, I will check your existing reservation and get back to you.
Ok.
Sorry, there is no reservation found on your name.
Ok, Thanks for the  information.
Thank you for choosing us, have a good day.