You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Donald White.

ASSISTANT: How may I assist you today?

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

ASSISTANT: Sure, please wait for a minute. I could not find a reservation with your name in our database.

USER: No problem, thank you for the information.

ASSISTANT: Welcome.