You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how shall I assist you?

USER: I want to cancel my reservation due to sudden change of plan. Can you please cancel my reservation on name Robert Turner?

ASSISTANT: Sure, give me some time.

USER: Ok.

ASSISTANT: Thanks for waiting, sorry to inform you that there is no reservation found with your name.

USER: Ok, no worries.

ASSISTANT: Thanks for choosing us, have a nice day.

USER: Thanks for your quick response.