You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I made a reservation to visit my family members, but I have got some urgent to attend. So, I would like to cancel my reservation. Can you help me in cancelling my reservation?

ASSISTANT: Sure, provide me your name to check the details of your reservation.

USER: My name is Dennis Johnson.

ASSISTANT: Dennis, there is no reservation found on your name in our database.

USER: I guess I didn't make any reservation. Anyways, thank you for the information.

ASSISTANT: May be, thank you for choosing us to serve you.

USER: Welcome.