You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, may I know your name?

USER: Anna Edwards here.

ASSISTANT: Give me a minute. Sorry, there is no reservation found under your name.

USER: Ok. That's ok. Thank you.

ASSISTANT: Thank you for reaching us.