You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: May I know your name please?

USER: Nicholas White here.

ASSISTANT: Please be on hold I will help you out with that.

USER: Sure.

ASSISTANT: No reservation found in our database as per your preferences.

USER: Ok, thank you.

ASSISTANT: Thank you for choosing us.