You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Gregory Wilson.

ASSISTANT: How can I aid you today?

USER: Due to some weather problems So I need to change my existing reservation, Can you please help me with that?

ASSISTANT: Sure. Please, wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you.