You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Dorothy Parker.

ASSISTANT: How may I help you?

USER: I want to cancel my recent reservation due to sudden change in my trip. Can you help me?

ASSISTANT: Sure, just wait a moment.

USER: Ok.

ASSISTANT: Sorry to inform you that there is no reservation exist on your name to cancel.

USER: No issue. Thank you for your help.

ASSISTANT: Thank you for reaching us.