You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: I am David Clark want to cancel my recent reservation due to sudden change in health condition.

ASSISTANT: Sure, wait for some time.

USER: Ok.

ASSISTANT: Thanks for waiting we are not found reservations on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thanks for choosing us, Have a good day.