You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I want to change my reservation, can you help me with that?

ASSISTANT: Sure, may I know your name for the changing process?

USER: Sure, Paul Rodriguez here.

ASSISTANT:  Sorry, we couldn't find a reservation on your name to change.

USER: No problem, thank you for the information.

ASSISTANT: Welcome, thank you for reaching us.