You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,.

USER: I am Barbara Adams.

ASSISTANT: By what way can I assist you today?

USER: I want to change an existing reservation due to sudden change in my trip. Can you help me?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: To proceed further, we need your name. Can you provide it? Ok, please wait.

USER: Ok.

ASSISTANT: Sorry Barbara Adams, there is no active reservation found on your name to change it.

USER: No issue. Thank you.

ASSISTANT: Ok, Thanks for approaching us.