You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Robert Wilson here, I need to change my previous booking. Can you help me?

ASSISTANT: Please wait a while. There is no reservation on your name in our database.

USER: Oh, That's fine, thank you for checking.

ASSISTANT: Do you want to know anything else?

USER: No, thank you for asking.

ASSISTANT: Thank you for choosing us.

USER: You are welcome.