You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I would like to change my existing reservation due to bad weather at my place. Can you help me with it?

ASSISTANT: Sure, kindly mention your name?

USER: Charles Johnson is my name.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry to say, no reservation found with your name.

USER: That's ok, thank you for the response.

ASSISTANT: Thanks for reaching us.