You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Due to sudden health issue, I am not able to travel in a flight. So, I would like to cancel my reservation. Can you please help me out with that?

ASSISTANT: May I know your name please?

USER: Sure, I have reserved it on the name of Brian Martinez.

ASSISTANT: No reservation found  in our database with your name.

USER: Oh! I think the ticket was cancelled by my cousin. Anyway, thank you for the information.

ASSISTANT: Thank you have a good day.

USER: Welcome.