You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Larry Green. I want to change my existing reservation due to heavy rain fall at my estination. Can you please help me with it?

ASSISTANT: Sure, please wait a minute.

USER: OK.

ASSISTANT: Sorry, to inform you that there is no reservation with your name.

USER: No problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your information.