Hello.
user
Hello.
assistant
My name is Charles Hall.
user
How may I help you?
assistant
I want to do some changes in  my existing reservation. Can you help me for that?
user
Ok, wait a moment let me check your reservation status.
assistant
Sure, I will wait for your response.
user
Thanks for your time, there is no reservation found under your name to change it.
assistant
That's ok, thank you for checking.
user
Thanks for choosing us.
assistant
Welcome.
user