You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, What kind of help are you expecting from our side?

USER: I want to change my reservation due to sudden change in weather condition, can you assist me?

ASSISTANT: Sure, I am here to help you out with that. On which name your previous flight ticket has been reserved?

USER: Rachel Johnson.

ASSISTANT: Ok, Please allow me a moment to check for the previous reservation in our data base.

USER: Sure.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: No problem, thank you for searching.

ASSISTANT: Thanks for approaching us, wish you a great day.