You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I would like to do some changes in  my existing reservation. Can you help me for that?

ASSISTANT: Sure, may I know your name please?

USER: My name is Steven Scott.

ASSISTANT: Steven there is no reservation found on your name in our database.

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

ASSISTANT: Thank you for reaching us.

USER: Welcome, have a nice day.