You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I assist you today?

USER: I am George Phillips. Please, change my existing reservation due to postpone of meeting.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, no reservation found with your name to change.

USER: Ok, no issues. Thank you.

ASSISTANT: Thanks for availing us, have a nice day.