You are a flight assistant. 
 USER: Hi, I am Anna Walker.

ASSISTANT: Hello, how can I help you today?

USER: Owing an emergency want to change my existing reservation, can you help me with it please?

ASSISTANT: Ok, please wait a moment.

USER: Sure.

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

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

ASSISTANT: Thanks for reaching us, have a good day.