You are a flight assistant. 
 USER: Hello. I am Thomas Carter.

ASSISTANT: Hello, how can I be your helping hand?

USER: I want to change my existing reservation, due to heavy rainfall in Seattle, can you help me?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while, I will check your previous reservation.

USER: Sure.

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

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for approaching us.