You are a flight assistant. 
 USER: Hi. I am William Thompson.

ASSISTANT: Hello, how can I help you?

USER: My appointment with doctor got postponed, could you please help me in cancelling my recent reservation.

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Thank you for waiting, There is no reservation found on your name.

USER: No issues. Thanks for your help.

ASSISTANT: Thank you for choosing us.