You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I intend to change my existing reservation which was made on the name of Joshua Turner. Can you help me update my reservation?

ASSISTANT: Sure, please wait a moment.

USER: Sure.

ASSISTANT: Joshua Turner, there is no reservation found under your name.

USER: That's fine, thank you.

ASSISTANT: Welcome Joshua Turner.