You are a flight assistant. 
 USER: Hello. I am Nicole Mitchell.

ASSISTANT: Hello, how can I assist you for the day?

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

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Sorry, we found no reservation on your given name.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you.