You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: Could you please help me to change an existing reservation as my trip got postpone due to my health issues?

ASSISTANT: Sure, I can help you out .

USER: Thank you.

ASSISTANT: May I know your name?

USER: I am Janet Rodriguez.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT:  Thanks for being waiting, We didn't found not reservation by this name.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for reaching us.