You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you?

USER: I had done my booking last week to meet my grand mother. But accidentally my grand mother came to my home.So, I would like to cancel my flight ticket. Can you help me?

ASSISTANT: Yes, sure. Firstly, can I know your name?

USER: Sure, my name is Benjamin Collins.

ASSISTANT: Sorry Collins, I did not find any reservation basing on your name.

USER: It's ok, no problem. Thank you for your information.

ASSISTANT: Do you have any other requirements?

USER: No thanks.

ASSISTANT: Ok, thank you for choosing our service.

USER: Welcome.