You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: My name is Nicole Hall. I want to do some changes in my existing reservation, can you help me for that?

ASSISTANT: Sure, please give me a minute.

USER: Ok, take your time.

ASSISTANT: Nicole, there is no reservation found with your details.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for choosing us.

USER: Welcome.