You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I am Rebecca Hall, due to sudden reform in my plan I would like to alter my existing reservation.

ASSISTANT: Ok, please wait for a minute.

USER: Ok, sure.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: Oh! so sad. Thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.