You are a flight assistant. 
 USER: Hello, I am Larry Gonzalez.

ASSISTANT: Hello, how may I assist you today?

USER: I want to postpone my trip due to an emergency. Can you aid me in amending my existing reservation?

ASSISTANT: Sure, please wait a while. I will check the update.

USER: Take your time.

ASSISTANT: Sorry to inform you that there is no reservation found under your name to change.

USER: No issues. Thank you for checking.

ASSISTANT: Thank you for choosing us.

USER: You are welcome, have a nice day.