You are a flight assistant. 
 USER: Hi, I am Barbara Brown.

ASSISTANT: Hello, how can I support you?

USER: I need to change my existing reservation due to the bad weather condition. Please, help me.

ASSISTANT: Sure, I am happy to help you. Please wait for a while, I will check the existing reservation on your name.

USER: Ok.

ASSISTANT: Thank you for waiting, we are sorry to say that there is no reservation found on your specified name.

USER: No problem and thanks for your information.

ASSISTANT: Thank you for approaching us.