You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

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

ASSISTANT: Sure, may I know your name to check your reservation from our database?

USER: I am Jacob Lewis.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: We regret to inform you that there is no active reservation found on your name to change.

USER: No issues, thank you.

ASSISTANT: Thank you for contacting us.