You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Brain Wright.

ASSISTANT:  How can I aid you?

USER: Please help me to change an existing reservation due to sudden demise of my great grand mother.

ASSISTANT: Ok, please wait I will revert you in a moment.

USER: Ok.

ASSISTANT:  Sorry, no reservation was found on your name.

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

ASSISTANT:  Thank you for availing us.