You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I want to change my reservation due to heavy rainfall at my place, can you please help me to change my reservation?

ASSISTANT: Sure, may I know your name to check the reservation?

USER: My name is Helen Allen.

ASSISTANT: Sorry, there is no reservation with your given name.

USER: Ok, thank you for notifying me.

ASSISTANT: Thank you for reaching us.