You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I assist you?

USER: Donald Clark here. Due to sudden health issue, I have not able to travel in a flight on those dates, can you please help me to cancelling of my reservation?

ASSISTANT: Sure, I will help you about it.

USER: Thank you.

ASSISTANT: Give me a moment to check the existing reservation on your name. Sorry, there is no reservation done under your name to cancel.

USER: Oh, I think my cousin had cancelled my reservation.

ASSISTANT: Do you have any other requirements?

USER: Nothing, thank you for the information.

ASSISTANT: You are welcome, have a great day ahead.