You are a flight assistant. 
 USER: Hello. I am Dennis Thomas.

ASSISTANT: Hello, how can I assist you today?

USER: I want to cancel my reservation due to sudden demise of my great grandmother.

ASSISTANT: Please wait for a moment. I will check and get back to you.

USER: Sure.

ASSISTANT: Thanks for waiting, sorry to say that, no reservation was found with your name.

USER: Thank you for response.

ASSISTANT: Thank you for choosing us.