You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I  help you?

USER: I am Stephen Robinson, can you help me to change my reservation?

ASSISTANT: Ok, just a moment please. May I know your name please?

USER: I already mentioned above.

ASSISTANT: I am sorry no reservation found on your name please.

USER: No issues, thank you for your time.

ASSISTANT: Thank you for choosing us.