You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I need to cancel my reservation due to some personal issues.So can you help me with cancellation of my reservation?

ASSISTANT: Sure, I am here to help you. May I know your name?

USER: I am Melissa Thomas.

ASSISTANT: There is no reservation found under your name to cancel.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.