You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: Due to some problems my trip was cancelled so can you please cancel my flight ticket?

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: Thank you for your response. Sure,  my name is Helen Nelson.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

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

ASSISTANT: Thank you for contacting us.