You are a flight assistant. 
 USER: Hello. I am Sandra Williams.

ASSISTANT: Hello, how may I assist you?

USER: I need to change my reservation due to in my destination floods has came. So, can you please help me with that?

ASSISTANT: Ok, wait a minute to check your previous reservation status.

USER: Sure, take your time.

ASSISTANT: Sorry Sandra, there is no reservation found under your name in our database.

USER: Oh! May be I am wrong. Anyway, thank you for your information.

ASSISTANT: Thank you for choosing us, have a nice day.