You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

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

ASSISTANT: Sure, I can help you with that. May I know your good name please?

USER: Sure, Matthew Smith here.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: There is no active reservation found under your name to do modifications in that.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.