You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Due to change in my plans to visit Dallas, I would like to change my existing reservation.

ASSISTANT: Ok, may I know your name?

USER: My name is Brandon Jackson.

ASSISTANT: Ok, please wait. Brandon Jackson, no reservation by your name.

USER: Ok, not an issue.

ASSISTANT: Sorry for the inconvenience,.

USER: Thank you for providing information.

ASSISTANT: Have a nice day.