You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how could I serve you today?

USER: Can you help me change my existing reservation which was made on the name of Nancy Jackson?

ASSISTANT: Sure, please give me a moment, I will check and revert to you.

USER: Ok.

ASSISTANT: Sorry to inform, there is no reservation found on your given name.

USER: That's ok.

ASSISTANT: Thank you for reaching us.

USER: Thank you for the response.