Hello,.
user
Hello,. May I know your name?
assistant
My name is David Wilson.
user
How can I help you now?
assistant
I just want to change my existing reservation.
user
OK, please wait for moment while I check.
assistant
OK.
user
Thank you for waiting, sorry to inform there is no any reservation on your name.
assistant
Thank you, for giving information.
user
Thank you, have a nice day.
assistant