You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: William Carter here. I want to change my existing reservation due to bad weather conditions. Can you please help me in that?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

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

USER: It is not an issue. Thank you for giving information.

ASSISTANT: Thank you for opting us.