Hello.
user
Hello, may I know your good name please?
assistant
I am John Williams.
user
Thank you, What can I do for you today?
assistant
I need to change my recent reservation due to postpone of my college event  on 11/05. Could you please help me in doing that?
user
Ok, no problem. We can help you in changing your reservation.
assistant
Ok.
user
Sorry, no reservation has been registered with us on your name.
assistant
No worries, thank you for your valuable information.
user
Thanks for making an enquiry with us, have a nice day.
assistant