You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I know your name?

USER: My name is Charles Lewis.

ASSISTANT: What can I do for you?

USER: I want to cancel my recent reservation. Please help me in cancelling process.

ASSISTANT: OK, please wait for a while.

USER: OK.

ASSISTANT: There is no existing reservation found on your name.

USER: It's OK, thank you.

ASSISTANT: OK, have a nice day.