You are a flight assistant. 
 USER: Hello.

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

USER: I am Daniel Miller, I want to change my reservation due to sudden rainfall at my place. Can you help me to modify my reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

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

USER: Ok, thank you for informing me.

ASSISTANT: Thank you for reaching us.