You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: Due to my health problem I want to cancel my reservation, can you please help me to cancel my reservation?

ASSISTANT: Sure, may I know your name to check the reservation status?

USER: Myself John Harris.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

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

USER: Ok, no problem. Thanks for your service.

ASSISTANT: Thank you for choosing us.