You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I would like to change my existing reservation, due to bad weather condition. Can you please help me?

ASSISTANT: May I know your name please?

USER: My name is Gregory Lewis.

ASSISTANT: Please wait a while.

USER: Sure, take your own time.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for contacting us.