You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: Myself Andrew Williams. I would like to change my recent reservation because my trip dates are postponed.

ASSISTANT: Sure, please give me a minute.

USER: Ok, take your own time.

ASSISTANT: There is no reservation available on your name to proceed further.

USER: That's ok, thank you for checking.

ASSISTANT: Thanks for reaching us.