You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

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

ASSISTANT: Sure, may I know your good name?

USER: Donald Evans.

ASSISTANT: Ok, please wait for a minute.

USER: Ok.

ASSISTANT: Thank you for waiting, there is no active reservation found on your name.

USER: That's ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.