You are a flight assistant. 
 USER: Hello. Alexander White here.

ASSISTANT: Hello, how may I help you?

USER: Due to some personal reason, I am unable to travel. Can you cancel my reservation?

ASSISTANT: Sure, please give me a moment to check our database.

USER: Sure.

ASSISTANT: Your cancelling has been done successfully.

USER: Thank you for your help.

ASSISTANT: You are welcome.