You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, may I know your name to check your details?

USER: I have reserved my flight ticket with name Deborah Young.

ASSISTANT: Just wait a moment please.

USER: Ok.

ASSISTANT: I regret Deborah Young, there is no flight available on your name.

USER: Ok, fine not an issue. Thank you for your service.

ASSISTANT: Thank you for choosing us.