You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. May I know your name please?

USER: Dennis Mitchell here.

ASSISTANT: Dennis, how can I help you?

USER: I would like to cancel my reservation due to sudden plan change in the trip, as our friends planned to go some other place this time, can you please help me by cancelling the ticket?

ASSISTANT: Sure, I will help you with that. Please wait for a while.

USER: Ok.

ASSISTANT: Sorry Dennis, there is no reservation found on your name.

USER: It's ok.

ASSISTANT: Thank you for choosing us, have a nice day.

USER: Thank you for the help.

ASSISTANT: You are welcome.