You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am Patrick Hernandez. I want to change an existing reservation, due to heavy rainfall. Can you please help me in changing reservation?

ASSISTANT: Sure Patrick, please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, there was no reservation found with your name.

USER: Not an issue. Thanks for your information.

ASSISTANT: Ok, thanks for choosing us.