You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Due to some personal issues, I would like to postpone my trip. Can you help me in changing my existing reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Ok, take your time.

ASSISTANT: May I know your good name please?

USER: My name is Brian Martinez.

ASSISTANT: Sorry, there is no reservation found on your name in our database to change.

USER: It's ok, no issues. Thank you for the information.

ASSISTANT: You are welcome.