You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I be of your service?

USER: I need to cancel my recent reservation on the name of David Roberts.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thanks for waiting. Unfortunately, there is no reservation found by your name.

USER: No problem. Thanks for the information.

ASSISTANT: Thank you for choosing us.