Hi. I am David Smith.
user
Hello, how may I help you today?
assistant
I want to change my existing reservation due to postpone of my board meeting, can you help with this?
user
Sure, please wait for a moment.
assistant
Sure.
user
Sorry to say that, there was no reservation found with your given name.
assistant
No problem, thank you for the information.
user
Thank you for opting us.
assistant