You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what help are you expecting from our agency side?

USER: Due to the sudden change in climate, I want to change my existing reservation?

ASSISTANT: I am here to help you out with all the concerns related to flight reservation. May I know the name on which you have booked your recent reservation please?

USER: Sure, I am Anthony Green.

ASSISTANT: Ok, give me a moment to check with your previous reservation status and revert back with available information.

USER: Sure.

ASSISTANT: I am very apologetic to inform you this news, but there is no active reservation found by your name in our agency database.

USER: Ok, not an issue. Thank you for your information.

ASSISTANT: Thank you for choosing our agency services. Have a nice day.