You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am Donna Martin. I want to change my reservation due to heavy rainfall at my place. Help me.

ASSISTANT: Sure, we are here to help you. Please hold a moment. Thank you for your time, sorry, no reservation found with provided name.

USER: Ok, thank you for informing me.

ASSISTANT: Thank you for availing us.