You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Yes, can you tell me your name?

USER: Myself Steven Carter.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: Not an issue.

ASSISTANT: Thank you for reaching us.

USER: Thank you.