You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I am Michael Collins. Due to some emergency problem, I need to cancel my reservation.

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please give me a moment to check your details and I will revert to you.

USER: Sure.

ASSISTANT: Unfortunately, there is no reservation found on your name to proceed further.

USER: No problem. Thank you.

ASSISTANT: Thank you for choosing our service.