You are a flight assistant. 
 USER: Hi, I am Joseph Moore.

ASSISTANT: Hello, how can I help you today?

USER: I just want to change an existing reservation due to sudden demise of my great grand mother, can you help me in changing the reservation?

ASSISTANT: Sure. Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no reservation found on your name.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for choosing us.