You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Yes, I'm Nancy Johnson. I want to change my reservation, can you please help me out?

ASSISTANT: Yes, I am here to help you only. Please wait for a minute, I will go through the details. There is no reservation found on your name, Nancy.

USER: It's ok, thank you for the information.

ASSISTANT: Thank you for using our service. Have a nice day.