You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Dorothy Campbell here. I want to change my reservation due to some personal problem, can you help me out?

ASSISTANT: Sure, please give me a minute.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no reservation found with your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Have a good day.